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Quick brute-force implementation of the Travelling Salesman Problem with Giraph
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Giraph : Travelling Salesman Problem
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On the left, we will show the original graph, to know how to process each step
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Giraph : Travelling Salesman Problem
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Superstep 0 begins
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Giraph : Travelling Salesman Problem
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Superstep 0 : we compute vertex n°1, nothing to do, it is not the source
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Giraph : Travelling Salesman Problem
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Superstep 0 : we compute vertex n°2, the source
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2,12+1
Giraph : Travelling Salesman Problem
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Superstep :
2,12+30
The source sends all the possible paths and their values to the others nodes
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2,12+1
Giraph : Travelling Salesman Problem
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2,12+30
The source then votes to halt
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2,12+1
Giraph : Travelling Salesman Problem
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2,12+30
Superstep 0 : we compute vertex n°3, nothing happens as it is not the source
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2,12+1
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Giraph : Travelling Salesman Problem
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2,12+30
12 12
Superstep 1 begins
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2,12+1
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Giraph : Travelling Salesman Problem
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1
2,12+30
12 12
Superstep 1 : we compute vertex n°1
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2,12+1
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Giraph : Travelling Salesman Problem
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2,12+30
21,42+10+23
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Superstep 1 : we compute vertex n°1
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2,12+1
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Giraph : Travelling Salesman Problem
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2,12+30
12 12
21,42+10+23
Superstep 1 : we compute vertex n°3
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2,12+1
12
Giraph : Travelling Salesman Problem
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30
1
2,12+30
12 12
23,13+10+33
21,42+10+23
Superstep 1 : we compute vertex n°3
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2,12+1
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Giraph : Travelling Salesman Problem
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30
1
2,12+30
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23,13+10+33
21,42+10+23
Superstep 2 begins
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2,12+1
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Giraph : Travelling Salesman Problem
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30
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2,12+30
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23,13+10+33
21,42+10+23
Superstep 2 : we compute vertex n°1
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2,12+1
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Giraph : Travelling Salesman Problem
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2,12+30
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23,13+10+33
21,42+10+23
231,56+30+23=109
Superstep 2 : we compute vertex n°1
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2,12+1
12
Giraph : Travelling Salesman Problem
10
30
1
2,12+30
12 12
23,13+10+33
21,42+10+23
231,56+30+23=109
Superstep 2 : we compute vertex n°3
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2,12+1
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Giraph : Travelling Salesman Problem
10
30
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2,12+30
12 12
23,13+10+33
21,42+10+23
231,56+30+23=109
213,75+10+33=118
Superstep 2 : we compute vertex n°3
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2,12+1
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Giraph : Travelling Salesman Problem
10
30
1
2,12+30
12 12
23,13+10+33
21,42+10+23
231,56+30+23=109
213,75+10+33=118
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Superstep 3 begins
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2,12+1
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Giraph : Travelling Salesman Problem
10
30
1
2,12+30
12 12
23,13+10+33
21,42+10+23
231,56+30+23=109
213,75+10+33=118
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Superstep 3 : we compute vertex n°1
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2,12+1
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Giraph : Travelling Salesman Problem
10
30
1
2,12+30
12 12
23,13+10+33
21,42+10+23
231,56+30+23=109
213,75+10+33=118
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Superstep 3 : we compute vertex n°1 : votes to Halt
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2,12+1
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Giraph : Travelling Salesman Problem
10
30
1
2,12+30
12 12
23,13+10+33
21,42+10+23
231,56+30+23=109
213,75+10+33=118
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Superstep 3 : we compute the source, reactivated by the messages received
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2,12+1
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Giraph : Travelling Salesman Problem
10
30
1
2,12+30
12 12
23,13+10+33
21,42+10+23
231,56+30+23=109
213,75+10+33=118
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The source compares the values received and finds the minimum distance
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109
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2,12+1
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Giraph : Travelling Salesman Problem
10
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2,12+30
12 12
23,13+10+33
21,42+10+23
231,56+30+23=109
213,75+10+33=118
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and sets its value as the minimum
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109
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2,12+1
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Giraph : Travelling Salesman Problem
10
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1
2,12+30
12 12
23,13+10+33
21,42+10+23
231,56+30+23=109
213,75+10+33=118
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109
The source then votes to Halt
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109
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2,12+1
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Giraph : Travelling Salesman Problem
10
30
1
2,12+30
12 12
23,13+10+33
21,42+10+23
231,56+30+23=109
213,75+10+33=118
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109
Superstep 3 : we compute vertex n°3
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109
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2,12+1
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Giraph : Travelling Salesman Problem
10
30
1
2,12+30
12 12
23,13+10+33
21,42+10+23
231,56+30+23=109
213,75+10+33=118
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109
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Superstep 3 : we compute vertex n°3 : votes to Halt, ends the process
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