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{{Infobox Algorithm
|class=[[Single-source shortest path problem]] (for weighted directed graphs)
|image=
|caption =
|data=[[Graph (data structure)|Graph]]
|time=<math>O (|V| |E|)</math>
|space=<math>O (|V|)</math>
}}
 
{{Tree search algorithm}}
 
The '''Bellman–Ford algorithm''' is an [[algorithm]] that computes [[shortest path]]s from a single source [[vertex (graph theory)|vertex]] to all of the other vertices in a [[weighted digraph]].<ref name=Bang>{{harvtxt|Bang-Jensen|Gutin|2000}}</ref>
It is slower than [[Dijkstra's algorithm]] for the same problem, but more versatile, as it is capable of handling graphs in which some of the edge weights are negative numbers.
The algorithm is usually named after two of its developers, [[Richard Bellman]] and [[L. R. Ford, Jr.|Lester Ford, Jr.]], who published it in 1958 and 1956, respectively; however, [[Edward F. Moore]] also published the same algorithm in 1957, and for this reason it is also sometimes called the '''Bellman–Ford–Moore algorithm'''.<ref name=Bang/>
 
Negative edge weights are found in various applications of graphs, hence the usefulness of this algorithm.{{sfnp|Sedgewick|2002}}
If a graph contains a "negative cycle" (i.e. a [[cycle (graph theory)|cycle]] whose edges sum to a negative value) that is reachable from the source, then there is no ''cheapest'' path: any path can be made cheaper by one more [[Walk (graph theory)|walk]] around the negative cycle. In such a case, the Bellman–Ford algorithm can detect negative cycles and report their existence. {{sfnp|Kleinberg|Tardos|2006}}<ref name=Bang/>
 
==Algorithm==
[[File:Bellman-Ford worst-case example.svg|thumb|In this example graph, assuming that A is the source and edges are processed in the worst order, from right to left, it requires the full &#124;V&#124;−1 or 4 iterations for the distance estimates to converge. Conversely, if the edges are processed in the best order, from left to right, the algorithm converges in a single iteration.]]
Like [[Dijkstra's Algorithm]], Bellman–Ford is based on the principle of [[Relaxation (approximation)|relaxation]], in which an approximation to the correct distance is gradually replaced by more accurate values until eventually reaching the optimum solution. In both algorithms, the approximate distance to each vertex is always an overestimate of the true distance, and is replaced by the minimum of its old value with the length of a newly found path.
However, Dijkstra's algorithm [[Greedy algorithm|greedily]] selects the minimum-weight node that has not yet been processed, and performs this relaxation process on all of its outgoing edges; in contrast, the Bellman–Ford algorithm simply relaxes ''all'' the edges, and does this |''V'' |&nbsp;&minus;&nbsp;1 times, where |''V'' | is the number of vertices in the graph. In each of these repetitions, the number of vertices with correctly calculated distances grows, from which it follows that eventually all vertices will have their correct distances. This method allows the Bellman–Ford algorithm to be applied to a wider class of inputs than Dijkstra.
 
Bellman–Ford runs in {{math| [[Big O notation|O]]({{!}} V {{!}} {{dot}} {{!}} E {{!}}) }} time, where {{math|{{!}} V {{!}} }} and {{math|{{!}} E {{!}} }} are the number of vertices and edges respectively.
 
'''procedure''' BellmanFord(''list'' vertices, ''list'' edges, ''vertex'' source)
    ''// This implementation takes in a graph, represented as lists of vertices and edges,''
    ''// and fills two arrays (distance and predecessor) with shortest-path information''
    ''// Step 1: initialize graph''
    '''for each''' vertex v '''in''' vertices:
        '''if''' v '''is''' source '''then''' distance[v] := 0
        '''else''' distance[v] := '''infinity'''
        predecessor[v] := '''null'''
    ''// Step 2: relax edges repeatedly''
    <!-- The outer loop iterates |V|-1 times. See, e.g, CLRS Ch. 24.1.  The value of i is unused. -->
    '''for''' i '''from''' 1 '''to''' size(vertices)-1:
        '''for each''' edge (u, v) '''with''' weight w '''in''' edges:
            '''if''' distance[u] + w < distance[v]:
                distance[v] := distance[u] + w
                predecessor[v] := u
    ''// Step 3: check for negative-weight cycles''
    '''for each''' edge (u, v) '''with''' weight w '''in''' edges:
        '''if''' distance[u] + w < distance[v]:
            '''error''' "Graph contains a negative-weight cycle"
 
==Proof of correctness==
 
The correctness of the algorithm can be shown by [[mathematical induction|induction]]. The precise statement shown by induction is:
 
'''Lemma'''. After ''i'' repetitions of ''for'' cycle:
* If Distance(''u'') is not infinity, it is equal to the length of some path from ''s'' to ''u'';
* If there is a path from ''s'' to ''u'' with at most ''i'' edges, then Distance(u) is at most the length of the shortest path from ''s'' to ''u'' with at most ''i'' edges.
 
'''Proof'''. For the base case of induction, consider <code>i=0</code> and the moment before ''for'' cycle is executed for the first time. Then, for the source vertex, <code>source.distance = 0</code>, which is correct. For other vertices ''u'', <code>u.distance = '''infinity'''</code>, which is also correct because there is no path from ''source'' to ''u'' with 0 edges.
 
For the inductive case, we first prove the first part. Consider a moment when a vertex's distance is updated by
<code>v.distance := u.distance + uv.weight</code>. By inductive assumption, <code>u.distance</code> is the length of some path from ''source'' to ''u''. Then <code>u.distance + uv.weight</code> is the length of the path from ''source'' to ''v'' that follows the path from  ''source'' to ''u'' and then goes to ''v''.
 
For the second part, consider the shortest path from ''source'' to ''u'' with at most ''i'' edges. Let ''v'' be the last vertex before ''u'' on this path. Then, the part of the path from ''source'' to ''v'' is the shortest path from ''source'' to ''v'' with at most ''i-1'' edges. By inductive assumption, <code>v.distance</code> after ''i''−1 cycles is at most the length of this path. Therefore, <code>uv.weight + v.distance</code> is at most the length of the path from ''s'' to ''u''. In the ''i<sup>th</sup>'' cycle, <code>u.distance</code> gets compared with <code>uv.weight + v.distance</code>, and is set equal to it if <code>uv.weight + v.distance</code> was smaller. Therefore, after ''i'' cycles, <code>u.distance</code> is at most the length of the shortest path from ''source'' to ''u'' that uses at most ''i'' edges.
 
If there are no negative-weight cycles, then every shortest path visits each vertex at most once, so at step 3 no further improvements can be made. Conversely, suppose no improvement can be made. Then for any cycle with vertices ''v''[0], ..., ''v''[''k''−1],
 
<code>v[i].distance <= v[(i-1) mod k].distance + v[(i-1) mod k]v[i].weight</code>
 
Summing around the cycle, the ''v''[''i''].distance terms and the ''v''[''i''−1 (mod ''k'')] distance terms cancel, leaving
 
<code>0 <= sum from 1 to k of v[i-1 (mod k)]v[i].weight</code>
 
I.e., every cycle has nonnegative weight.
 
==Finding negative cycles==
When the algorithm is used to find shortest paths, the existence of negative cycles is a problem, preventing the algorithm from finding a correct answer. However, since it terminates upon finding a negative cycle, the Bellman–Ford algorithm can be used for applications in which this is the target to be sought - for example in [[cycle-cancelling]] techniques in [[Flow network|network flow]] analysis.<ref name="Bang"/>
 
== Applications in routing ==
 
A distributed variant of the Bellman–Ford algorithm is used in [[distance-vector routing protocol]]s, for example the [[Routing Information Protocol]] (RIP). The algorithm is distributed because it involves a number of nodes (routers) within an [[autonomous system (Internet)|Autonomous system]], a collection of IP networks typically owned by an ISP.
It consists of the following steps:
 
# Each node calculates the distances between itself and all other nodes within the AS and stores this information as a table.
# Each node sends its table to all neighboring nodes.
# When a node receives distance tables from its neighbors, it calculates the shortest routes to all other nodes and updates its own table to reflect any changes.
 
The main disadvantages of the Bellman–Ford algorithm in this setting are as follows:
 
* It does not scale well.
* Changes in [[network topology]] are not reflected quickly since updates are spread node-by-node.
* [[Count to infinity#Count-to-infinity problem|Count to infinity]] (if link or node failures render a node unreachable from some set of other nodes, those nodes may spend forever gradually increasing their estimates of the distance to it, and in the meantime there may be routing loops).
 
==Improvements==
The Bellman–Ford algorithm may be improved in practice (although not in the worst case) by the observation that, if an iteration of the main loop of the algorithm terminates without making any changes, the algorithm can be immediately terminated, as subsequent iterations will not make any more changes. With this early termination condition, the main loop may in some cases use many fewer than |''V''|&nbsp;&minus;&nbsp;1 iterations, even though the worst case of the algorithm remains unchanged.
 
{{harvtxt|Yen|1970}} described two more improvements to the Bellman–Ford algorithm for a graph without negative-weight cycles; again, while making the algorithm faster in practice, they do not change its O(|V|*|E|) worst case time bound. His first improvement reduces the number of relaxation steps that need to be performed within each iteration of the algorithm. If a vertex ''v'' has a distance value that has not changed since the last time the edges out of ''v'' were relaxed, then there is no need to relax the edges out of ''v'' a second time. In this way, as the number of vertices with correct distance values grows, the number whose outgoing edges need to be relaxed in each iteration shrinks, leading to a constant-factor savings in time for [[dense graph]]s.
 
Yen's second improvement first assigns some arbitrary linear order on all vertices and then partitions the set of all edges into two subsets. The first subset, ''E<sub>f</sub>'', contains all edges (''v<sub>i</sub>'', ''v<sub>j</sub>'') such that ''i'' < ''j''; the second, ''E<sub>b</sub>'', contains edges (''v<sub>i</sub>'', ''v<sub>j</sub>'') such that ''i'' > ''j''. Each vertex is visited in the order ''v<sub>1</sub>'', ''v<sub>2</sub>'', ..., ''v''<sub>|''V''|</sub>, relaxing each outgoing edge from that vertex in ''E<sub>f</sub>''. Each vertex is then visited in the order ''v''<sub>|''V''|</sub>, ''v''<sub>|''V''|−1</sub>, ..., ''v''<sub>1</sub>, relaxing each outgoing edge from that vertex in ''E<sub>b</sub>''. Each iteration of the main loop of the algorithm, after the first one, adds at least two edges to the set of edges whose relaxed distances match the correct shortest path distances: one from ''E<sub>f</sub>'' and one from ''E<sub>b</sub>''. This modification reduces the worst-case number of iterations of the main loop of the algorithm from |''V''|&nbsp;&minus;&nbsp;1 to |''V''|/2.<ref>Cormen et al., 2nd ed., Problem 24-1, pp. 614–615.</ref><ref name=Sedweb/>
 
Another improvement, by {{harvtxt|Bannister|Eppstein|2012}}, replaces the arbitrary linear order of the vertices used in Yen's second improvement by a [[random permutation]]. This change makes the worst case for Yen's improvement (in which the edges of a shortest path strictly alternate between the two subsets ''E<sub>f</sub>'' and ''E<sub>b</sub>'') very unlikely to happen. With a randomly permuted vertex ordering, the [[expected value|expected]] number of iterations needed in the main loop is at most |''V''|/3.<ref name=Sedweb>See Sedgewick's [http://algs4.cs.princeton.edu/44sp/ web exercises] for ''Algorithms'', 4th ed., exercises 5 and 11 (retrieved 2013-01-30).</ref>
 
==Notes==
{{Reflist}}
 
==References==
 
===Original sources===
*{{cite journal
| last = Bellman | first = Richard | authorlink = Richard Bellman
| mr = 0102435
| journal = Quarterly of Applied Mathematics
| pages = 87–90
| title = On a routing problem
| volume = 16
| year = 1958
| ref = harv}}
*{{cite book
|authorlink=L. R. Ford, Jr. | last=Ford Jr. | first=Lester R.
|title=Network Flow Theory
|date=August 14, 1956
|series=Paper P-923
|publisher=RAND Corporation
|location=Santa Monica, California
|url=http://www.rand.org/pubs/papers/P923.html}}
*{{cite conference
| last = Moore | first = Edward F. | authorlink = Edward F. Moore
| title = The shortest path through a maze
| location = Cambridge, Mass.
| mr = 0114710
| pages = 285–292
| publisher = Harvard Univ. Press
| booktitle = Proc. Internat. Sympos. Switching Theory 1957, Part II
| year = 1959
| ref = harv}}
*{{cite journal
| last = Yen | first = Jin Y.
| mr = 0253822
| journal = Quarterly of Applied Mathematics
| pages = 526–530
| title = An algorithm for finding shortest routes from all source nodes to a given destination in general networks
| volume = 27
| year = 1970
| ref = harv}}
*{{cite conference|title=Randomized speedup of the Bellman–Ford algorithm|first1=M. J.|last1=Bannister|first2=D.|last2=Eppstein|author2-link=David Eppstein|arxiv=1111.5414|booktitle=Analytic Algorithmics and Combinatorics (ANALCO12), Kyoto, Japan|year=2012|pages=41–47|url=http://siam.omnibooksonline.com/2012ANALCO/data/papers/005.pdf|ref=harv}}
 
===Secondary sources===
*{{Cite book|first1=Jørgen |last1=Bang-Jensen|first2=Gregory|last2=Gutin|year=2000|title=Digraphs: Theory, Algorithms and Applications|edition=First |isbn=978-1-84800-997-4|chapter=Section 2.3.4: The Bellman-Ford-Moore algorithm|url=http://www.cs.rhul.ac.uk/books/dbook/|ref=harv}}
*{{Introduction to Algorithms}}, Second Edition. MIT Press and McGraw-Hill, 2001. ISBN 0-262-03293-7. Section 24.1: The Bellman–Ford algorithm, pp.&nbsp;588&ndash;592. Problem 24-1, pp.&nbsp;614&ndash;615. Third Edition. MIT Press, 2009. ISBN 978-0-262-53305-8. Section 24.1: The Bellman–Ford algorithm, pp.&nbsp;651&ndash;655.
*{{cite book | first1 = George T. | last1 = Heineman | first2 = Gary | last2 = Pollice | first3 = Stanley | last3 = Selkow | title= Algorithms in a Nutshell | publisher=[[O'Reilly Media]] | year=2008 | chapter=Chapter 6: Graph Algorithms | pages = 160–164 | isbn=978-0-596-51624-6 | ref = harv }}
*{{cite book|last1=Kleinberg|first1=Jon|author1-link=Jon Kleinberg|last2=Tardos|first2=Éva|author2-link=Éva Tardos|year=2006|title=Algorithm Design|location=New York|publisher=Pearson Education, Inc.|ref=harv}}
*{{Cite book|first=Robert |last=Sedgewick|authorlink=Robert Sedgewick (computer scientist)|year=2002|title= Algorithms in Java|edition=3rd |isbn= 0-201-36121-3|chapter=Section 21.7: Negative Edge Weights|url=http://safari.oreilly.com/0201361213/ch21lev1sec7|ref=harv}}
 
==External links==
* [https://github.com/xtaci/algorithms/blob/master/include/bellman_ford.h C++ code example]
* [http://code.google.com/p/annas/ Open Source Java Graph package with Bellman-Ford Algorithms]
 
{{DEFAULTSORT:Bellman-Ford algorithm}}
[[Category:Graph algorithms]]
[[Category:Polynomial-time problems]]
[[Category:Articles with example C code]]
[[Category:Articles with example pseudocode]]
[[Category:Dynamic programming]]

Revision as of 05:13, 1 December 2013

Template:Infobox Algorithm

Template:Tree search algorithm

The Bellman–Ford algorithm is an algorithm that computes shortest paths from a single source vertex to all of the other vertices in a weighted digraph.[1] It is slower than Dijkstra's algorithm for the same problem, but more versatile, as it is capable of handling graphs in which some of the edge weights are negative numbers. The algorithm is usually named after two of its developers, Richard Bellman and Lester Ford, Jr., who published it in 1958 and 1956, respectively; however, Edward F. Moore also published the same algorithm in 1957, and for this reason it is also sometimes called the Bellman–Ford–Moore algorithm.[1]

Negative edge weights are found in various applications of graphs, hence the usefulness of this algorithm.Template:Sfnp If a graph contains a "negative cycle" (i.e. a cycle whose edges sum to a negative value) that is reachable from the source, then there is no cheapest path: any path can be made cheaper by one more walk around the negative cycle. In such a case, the Bellman–Ford algorithm can detect negative cycles and report their existence. Template:Sfnp[1]

Algorithm

In this example graph, assuming that A is the source and edges are processed in the worst order, from right to left, it requires the full |V|−1 or 4 iterations for the distance estimates to converge. Conversely, if the edges are processed in the best order, from left to right, the algorithm converges in a single iteration.

Like Dijkstra's Algorithm, Bellman–Ford is based on the principle of relaxation, in which an approximation to the correct distance is gradually replaced by more accurate values until eventually reaching the optimum solution. In both algorithms, the approximate distance to each vertex is always an overestimate of the true distance, and is replaced by the minimum of its old value with the length of a newly found path. However, Dijkstra's algorithm greedily selects the minimum-weight node that has not yet been processed, and performs this relaxation process on all of its outgoing edges; in contrast, the Bellman–Ford algorithm simply relaxes all the edges, and does this |V | − 1 times, where |V | is the number of vertices in the graph. In each of these repetitions, the number of vertices with correctly calculated distances grows, from which it follows that eventually all vertices will have their correct distances. This method allows the Bellman–Ford algorithm to be applied to a wider class of inputs than Dijkstra.

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This feature is suitable for you who need to get the tax deductions out of your PIC scheme to your property agency firm. It's endorsed that you visit the correct site for filling this tax return software. This utility must be submitted at the very least yearly to report your whole tax and tax return that you're going to receive in the current accounting 12 months. There may be an official website for this tax filling procedure. Filling this tax return software shouldn't be a tough thing to do for all business homeowners in Singapore.

A wholly owned subsidiary of SLP Worldwide, SLP Realty houses 900 associates to service SLP's fast rising portfolio of residential tasks. Real estate is a human-centric trade. Apart from offering comprehensive coaching applications for our associates, SLP Realty puts equal emphasis on creating human capabilities and creating sturdy teamwork throughout all ranges of our organisational hierarchy. Worldwide Presence At SLP International, our staff of execs is pushed to make sure our shoppers meet their enterprise and investment targets. Under is an inventory of some notable shoppers from completely different industries and markets, who've entrusted their real estate must the expertise of SLP Worldwide.

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procedure BellmanFord(list vertices, list edges, vertex source)
   // This implementation takes in a graph, represented as lists of vertices and edges,
   // and fills two arrays (distance and predecessor) with shortest-path information

   // Step 1: initialize graph
   for each vertex v in vertices:
       if v is source then distance[v] := 0
       else distance[v] := infinity
       predecessor[v] := null

   // Step 2: relax edges repeatedly
   for i from 1 to size(vertices)-1:
       for each edge (u, v) with weight w in edges:
           if distance[u] + w < distance[v]:
               distance[v] := distance[u] + w
               predecessor[v] := u

   // Step 3: check for negative-weight cycles
   for each edge (u, v) with weight w in edges:
       if distance[u] + w < distance[v]:
           error "Graph contains a negative-weight cycle"

Proof of correctness

The correctness of the algorithm can be shown by induction. The precise statement shown by induction is:

Lemma. After i repetitions of for cycle:

  • If Distance(u) is not infinity, it is equal to the length of some path from s to u;
  • If there is a path from s to u with at most i edges, then Distance(u) is at most the length of the shortest path from s to u with at most i edges.

Proof. For the base case of induction, consider i=0 and the moment before for cycle is executed for the first time. Then, for the source vertex, source.distance = 0, which is correct. For other vertices u, u.distance = infinity, which is also correct because there is no path from source to u with 0 edges.

For the inductive case, we first prove the first part. Consider a moment when a vertex's distance is updated by v.distance := u.distance + uv.weight. By inductive assumption, u.distance is the length of some path from source to u. Then u.distance + uv.weight is the length of the path from source to v that follows the path from source to u and then goes to v.

For the second part, consider the shortest path from source to u with at most i edges. Let v be the last vertex before u on this path. Then, the part of the path from source to v is the shortest path from source to v with at most i-1 edges. By inductive assumption, v.distance after i−1 cycles is at most the length of this path. Therefore, uv.weight + v.distance is at most the length of the path from s to u. In the ith cycle, u.distance gets compared with uv.weight + v.distance, and is set equal to it if uv.weight + v.distance was smaller. Therefore, after i cycles, u.distance is at most the length of the shortest path from source to u that uses at most i edges.

If there are no negative-weight cycles, then every shortest path visits each vertex at most once, so at step 3 no further improvements can be made. Conversely, suppose no improvement can be made. Then for any cycle with vertices v[0], ..., v[k−1],

v[i].distance <= v[(i-1) mod k].distance + v[(i-1) mod k]v[i].weight

Summing around the cycle, the v[i].distance terms and the v[i−1 (mod k)] distance terms cancel, leaving

0 <= sum from 1 to k of v[i-1 (mod k)]v[i].weight

I.e., every cycle has nonnegative weight.

Finding negative cycles

When the algorithm is used to find shortest paths, the existence of negative cycles is a problem, preventing the algorithm from finding a correct answer. However, since it terminates upon finding a negative cycle, the Bellman–Ford algorithm can be used for applications in which this is the target to be sought - for example in cycle-cancelling techniques in network flow analysis.[1]

Applications in routing

A distributed variant of the Bellman–Ford algorithm is used in distance-vector routing protocols, for example the Routing Information Protocol (RIP). The algorithm is distributed because it involves a number of nodes (routers) within an Autonomous system, a collection of IP networks typically owned by an ISP. It consists of the following steps:

  1. Each node calculates the distances between itself and all other nodes within the AS and stores this information as a table.
  2. Each node sends its table to all neighboring nodes.
  3. When a node receives distance tables from its neighbors, it calculates the shortest routes to all other nodes and updates its own table to reflect any changes.

The main disadvantages of the Bellman–Ford algorithm in this setting are as follows:

  • It does not scale well.
  • Changes in network topology are not reflected quickly since updates are spread node-by-node.
  • Count to infinity (if link or node failures render a node unreachable from some set of other nodes, those nodes may spend forever gradually increasing their estimates of the distance to it, and in the meantime there may be routing loops).

Improvements

The Bellman–Ford algorithm may be improved in practice (although not in the worst case) by the observation that, if an iteration of the main loop of the algorithm terminates without making any changes, the algorithm can be immediately terminated, as subsequent iterations will not make any more changes. With this early termination condition, the main loop may in some cases use many fewer than |V| − 1 iterations, even though the worst case of the algorithm remains unchanged.

Template:Harvtxt described two more improvements to the Bellman–Ford algorithm for a graph without negative-weight cycles; again, while making the algorithm faster in practice, they do not change its O(|V|*|E|) worst case time bound. His first improvement reduces the number of relaxation steps that need to be performed within each iteration of the algorithm. If a vertex v has a distance value that has not changed since the last time the edges out of v were relaxed, then there is no need to relax the edges out of v a second time. In this way, as the number of vertices with correct distance values grows, the number whose outgoing edges need to be relaxed in each iteration shrinks, leading to a constant-factor savings in time for dense graphs.

Yen's second improvement first assigns some arbitrary linear order on all vertices and then partitions the set of all edges into two subsets. The first subset, Ef, contains all edges (vi, vj) such that i < j; the second, Eb, contains edges (vi, vj) such that i > j. Each vertex is visited in the order v1, v2, ..., v|V|, relaxing each outgoing edge from that vertex in Ef. Each vertex is then visited in the order v|V|, v|V|−1, ..., v1, relaxing each outgoing edge from that vertex in Eb. Each iteration of the main loop of the algorithm, after the first one, adds at least two edges to the set of edges whose relaxed distances match the correct shortest path distances: one from Ef and one from Eb. This modification reduces the worst-case number of iterations of the main loop of the algorithm from |V| − 1 to |V|/2.[2][3]

Another improvement, by Template:Harvtxt, replaces the arbitrary linear order of the vertices used in Yen's second improvement by a random permutation. This change makes the worst case for Yen's improvement (in which the edges of a shortest path strictly alternate between the two subsets Ef and Eb) very unlikely to happen. With a randomly permuted vertex ordering, the expected number of iterations needed in the main loop is at most |V|/3.[3]

Notes

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References

Original sources

  • One of the biggest reasons investing in a Singapore new launch is an effective things is as a result of it is doable to be lent massive quantities of money at very low interest rates that you should utilize to purchase it. Then, if property values continue to go up, then you'll get a really high return on funding (ROI). Simply make sure you purchase one of the higher properties, reminiscent of the ones at Fernvale the Riverbank or any Singapore landed property Get Earnings by means of Renting

    In its statement, the singapore property listing - website link, government claimed that the majority citizens buying their first residence won't be hurt by the new measures. Some concessions can even be prolonged to chose teams of consumers, similar to married couples with a minimum of one Singaporean partner who are purchasing their second property so long as they intend to promote their first residential property. Lower the LTV limit on housing loans granted by monetary establishments regulated by MAS from 70% to 60% for property purchasers who are individuals with a number of outstanding housing loans on the time of the brand new housing purchase. Singapore Property Measures - 30 August 2010 The most popular seek for the number of bedrooms in Singapore is 4, followed by 2 and three. Lush Acres EC @ Sengkang

    Discover out more about real estate funding in the area, together with info on international funding incentives and property possession. Many Singaporeans have been investing in property across the causeway in recent years, attracted by comparatively low prices. However, those who need to exit their investments quickly are likely to face significant challenges when trying to sell their property – and could finally be stuck with a property they can't sell. Career improvement programmes, in-house valuation, auctions and administrative help, venture advertising and marketing, skilled talks and traisning are continuously planned for the sales associates to help them obtain better outcomes for his or her shoppers while at Knight Frank Singapore. No change Present Rules

    Extending the tax exemption would help. The exemption, which may be as a lot as $2 million per family, covers individuals who negotiate a principal reduction on their existing mortgage, sell their house short (i.e., for lower than the excellent loans), or take part in a foreclosure course of. An extension of theexemption would seem like a common-sense means to assist stabilize the housing market, but the political turmoil around the fiscal-cliff negotiations means widespread sense could not win out. Home Minority Chief Nancy Pelosi (D-Calif.) believes that the mortgage relief provision will be on the table during the grand-cut price talks, in response to communications director Nadeam Elshami. Buying or promoting of blue mild bulbs is unlawful.

    A vendor's stamp duty has been launched on industrial property for the primary time, at rates ranging from 5 per cent to 15 per cent. The Authorities might be trying to reassure the market that they aren't in opposition to foreigners and PRs investing in Singapore's property market. They imposed these measures because of extenuating components available in the market." The sale of new dual-key EC models will even be restricted to multi-generational households only. The models have two separate entrances, permitting grandparents, for example, to dwell separately. The vendor's stamp obligation takes effect right this moment and applies to industrial property and plots which might be offered inside three years of the date of buy. JLL named Best Performing Property Brand for second year running

    The data offered is for normal info purposes only and isn't supposed to be personalised investment or monetary advice. Motley Fool Singapore contributor Stanley Lim would not personal shares in any corporations talked about. Singapore private home costs increased by 1.eight% within the fourth quarter of 2012, up from 0.6% within the earlier quarter. Resale prices of government-built HDB residences which are usually bought by Singaporeans, elevated by 2.5%, quarter on quarter, the quickest acquire in five quarters. And industrial property, prices are actually double the levels of three years ago. No withholding tax in the event you sell your property. All your local information regarding vital HDB policies, condominium launches, land growth, commercial property and more

    There are various methods to go about discovering the precise property. Some local newspapers (together with the Straits Instances ) have categorised property sections and many local property brokers have websites. Now there are some specifics to consider when buying a 'new launch' rental. Intended use of the unit Every sale begins with 10 p.c low cost for finish of season sale; changes to 20 % discount storewide; follows by additional reduction of fiftyand ends with last discount of 70 % or extra. Typically there is even a warehouse sale or transferring out sale with huge mark-down of costs for stock clearance. Deborah Regulation from Expat Realtor shares her property market update, plus prime rental residences and houses at the moment available to lease Esparina EC @ Sengkang
  • 20 year-old Real Estate Agent Rusty from Saint-Paul, has hobbies and interests which includes monopoly, property developers in singapore and poker. Will soon undertake a contiki trip that may include going to the Lower Valley of the Omo.

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  • 55 years old Systems Administrator Antony from Clarence Creek, really loves learning, PC Software and aerobics. Likes to travel and was inspired after making a journey to Historic Ensemble of the Potala Palace.

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  • One of the biggest reasons investing in a Singapore new launch is an effective things is as a result of it is doable to be lent massive quantities of money at very low interest rates that you should utilize to purchase it. Then, if property values continue to go up, then you'll get a really high return on funding (ROI). Simply make sure you purchase one of the higher properties, reminiscent of the ones at Fernvale the Riverbank or any Singapore landed property Get Earnings by means of Renting

    In its statement, the singapore property listing - website link, government claimed that the majority citizens buying their first residence won't be hurt by the new measures. Some concessions can even be prolonged to chose teams of consumers, similar to married couples with a minimum of one Singaporean partner who are purchasing their second property so long as they intend to promote their first residential property. Lower the LTV limit on housing loans granted by monetary establishments regulated by MAS from 70% to 60% for property purchasers who are individuals with a number of outstanding housing loans on the time of the brand new housing purchase. Singapore Property Measures - 30 August 2010 The most popular seek for the number of bedrooms in Singapore is 4, followed by 2 and three. Lush Acres EC @ Sengkang

    Discover out more about real estate funding in the area, together with info on international funding incentives and property possession. Many Singaporeans have been investing in property across the causeway in recent years, attracted by comparatively low prices. However, those who need to exit their investments quickly are likely to face significant challenges when trying to sell their property – and could finally be stuck with a property they can't sell. Career improvement programmes, in-house valuation, auctions and administrative help, venture advertising and marketing, skilled talks and traisning are continuously planned for the sales associates to help them obtain better outcomes for his or her shoppers while at Knight Frank Singapore. No change Present Rules

    Extending the tax exemption would help. The exemption, which may be as a lot as $2 million per family, covers individuals who negotiate a principal reduction on their existing mortgage, sell their house short (i.e., for lower than the excellent loans), or take part in a foreclosure course of. An extension of theexemption would seem like a common-sense means to assist stabilize the housing market, but the political turmoil around the fiscal-cliff negotiations means widespread sense could not win out. Home Minority Chief Nancy Pelosi (D-Calif.) believes that the mortgage relief provision will be on the table during the grand-cut price talks, in response to communications director Nadeam Elshami. Buying or promoting of blue mild bulbs is unlawful.

    A vendor's stamp duty has been launched on industrial property for the primary time, at rates ranging from 5 per cent to 15 per cent. The Authorities might be trying to reassure the market that they aren't in opposition to foreigners and PRs investing in Singapore's property market. They imposed these measures because of extenuating components available in the market." The sale of new dual-key EC models will even be restricted to multi-generational households only. The models have two separate entrances, permitting grandparents, for example, to dwell separately. The vendor's stamp obligation takes effect right this moment and applies to industrial property and plots which might be offered inside three years of the date of buy. JLL named Best Performing Property Brand for second year running

    The data offered is for normal info purposes only and isn't supposed to be personalised investment or monetary advice. Motley Fool Singapore contributor Stanley Lim would not personal shares in any corporations talked about. Singapore private home costs increased by 1.eight% within the fourth quarter of 2012, up from 0.6% within the earlier quarter. Resale prices of government-built HDB residences which are usually bought by Singaporeans, elevated by 2.5%, quarter on quarter, the quickest acquire in five quarters. And industrial property, prices are actually double the levels of three years ago. No withholding tax in the event you sell your property. All your local information regarding vital HDB policies, condominium launches, land growth, commercial property and more

    There are various methods to go about discovering the precise property. Some local newspapers (together with the Straits Instances ) have categorised property sections and many local property brokers have websites. Now there are some specifics to consider when buying a 'new launch' rental. Intended use of the unit Every sale begins with 10 p.c low cost for finish of season sale; changes to 20 % discount storewide; follows by additional reduction of fiftyand ends with last discount of 70 % or extra. Typically there is even a warehouse sale or transferring out sale with huge mark-down of costs for stock clearance. Deborah Regulation from Expat Realtor shares her property market update, plus prime rental residences and houses at the moment available to lease Esparina EC @ Sengkang
  • 55 years old Systems Administrator Antony from Clarence Creek, really loves learning, PC Software and aerobics. Likes to travel and was inspired after making a journey to Historic Ensemble of the Potala Palace.

    You can view that web-site... ccleaner free download

Secondary sources

  • 20 year-old Real Estate Agent Rusty from Saint-Paul, has hobbies and interests which includes monopoly, property developers in singapore and poker. Will soon undertake a contiki trip that may include going to the Lower Valley of the Omo.

    My blog: http://www.primaboinca.com/view_profile.php?userid=5889534
  • Template:Introduction to Algorithms, Second Edition. MIT Press and McGraw-Hill, 2001. ISBN 0-262-03293-7. Section 24.1: The Bellman–Ford algorithm, pp. 588–592. Problem 24-1, pp. 614–615. Third Edition. MIT Press, 2009. ISBN 978-0-262-53305-8. Section 24.1: The Bellman–Ford algorithm, pp. 651–655.
  • 20 year-old Real Estate Agent Rusty from Saint-Paul, has hobbies and interests which includes monopoly, property developers in singapore and poker. Will soon undertake a contiki trip that may include going to the Lower Valley of the Omo.

    My blog: http://www.primaboinca.com/view_profile.php?userid=5889534
  • 20 year-old Real Estate Agent Rusty from Saint-Paul, has hobbies and interests which includes monopoly, property developers in singapore and poker. Will soon undertake a contiki trip that may include going to the Lower Valley of the Omo.

    My blog: http://www.primaboinca.com/view_profile.php?userid=5889534
  • 20 year-old Real Estate Agent Rusty from Saint-Paul, has hobbies and interests which includes monopoly, property developers in singapore and poker. Will soon undertake a contiki trip that may include going to the Lower Valley of the Omo.

    My blog: http://www.primaboinca.com/view_profile.php?userid=5889534

External links

  1. 1.0 1.1 1.2 1.3 Template:Harvtxt
  2. Cormen et al., 2nd ed., Problem 24-1, pp. 614–615.
  3. 3.0 3.1 See Sedgewick's web exercises for Algorithms, 4th ed., exercises 5 and 11 (retrieved 2013-01-30).