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Breadth first search animation

Network Optimization

Breadth First Search

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Breadth first search animation 2

Initialize

LIST

Unmark allnodes in N;

1

2 4

5

3 6 9

7

8

1

2 4

5

3 6 9

7

8

11

Mark node 1

and add it to

LIST.

1

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Breadth first search animation 3

Select node 1

LIST

Select thefirst node

in LIST.

1

2 4

5

3 6 9

7

8

1

1

1

1

1

2

3

Arc numbers for arcs in A(i) refer to the

order in which arcs of A(i) are scanned.

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Breadth first search animation 4

Scan arcs (1,2)

LIST

1

2 4

5

3 6 9

7

8

1

1

1

1

Find an

admissible

arc

22

2

1

2

3

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Breadth first search animation 5

Scan arc (1,5)

LIST

1

2 4

5

3 6 9

7

8

3

1

1

1

1

22

2 5

5

Select node 1

and find an

admissible

arc.

1

2

3

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Breadth first search animation 6

4

Scan arc (1,3)

LIST

1

2 4

5

3 6 9

7

8

3

1

1

1

1

22

2 5

5

3

3

Select node 1

and find an

admissible

arc.

1

2

3

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Breadth first search animation 7

4

Delete Node 1 from LIST

LIST

Delete node 1

from LIST

1

2 4

5

3 6 9

7

8

31

1

1 1

22

2 5

5

3

3

1

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Breadth first search animation 8

4

Select Node 2

LIST

Select first

node on LIST

1

2 4

5

3 6 9

7

8

31

1

1 1

22

2 5

5

3

3

1

21

2

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Breadth first search animation 9

5

4

Scan arc (2, 4)

LIST

1

2 4

5

3 6 9

7

8

31

1

1

22

2 5

5

3

3

2

Select anadmissible

arc

4

4

1

2

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Breadth first search animation 10

5

4

Scan arc (2, 5)

LIST

1

2 4

5

3 6 9

7

8

31

1

1

22

2 5

5

3

3

2

Ignore anyscanned arcs

out of node 2

that are not

admissible.

4

4

1

2

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Breadth first search animation 11

5

4

Delete node 2

LIST

1

2 4

5

3 6 9

7

8

311

22

2 5

5

3

3

2

Delete node 2

from LIST

4

4

2

1

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Breadth first search animation 12

5

4

Select node 5

LIST

1

2 4

5

3 6 9

7

8

311

22

5

5

3

3

2 4

4

Select thefirst node on

LIST

5

1

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Breadth first search animation 13

6

5

4

Scan arc (5,6)

LIST

1

2 4

5

3 6 9

7

8

311

22

5

5

3

3

2 4

4

5

Find an

admissible

arc6

6

1

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Breadth first search animation 14

6

5

4

Delete node 5

LIST

1

2 4

5

3 6 9

7

8

311

22

5

5

3

3

2 4

4

5

6

6

Delete node 5

from LIST

5

1

2

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Breadth first search animation 15

6

5

4

Select node 3

LIST

1

2 4

5

3 6 9

7

8

311

22

5

3

3

2 4

4

5

6

6

Select first

node on LIST

5

3

1

2

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Breadth first search animation 16

6

5

4

Scan arcs out of node 3

LIST

1

2 4

5

3 6 9

7

8

311

22

5

3

3

2 4

4

5

6

6

Ignore any

scanned arc

that is not

admissible.

5

3

1

2

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Breadth first search animation 17

6

5

4

Delete node 3

LIST

1

2 4

5

3 6 9

7

8

311

22

5

3

3

2 4

4

5

6

6

Delete node 3

from LIST

5

33

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Breadth first search animation 18

6

5

4

Select node 4

LIST

1

2 4

5

3 6 9

7

8

311

22

5

3

4

4

6

6

Select thefirst node on

LIST

41

2

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Breadth first search animation 19

7

6

5

4

Scan arc (4, 8)

LIST

1

2 4

5

3 6 9

7

8

31

1

1

22

2 5

5

3

3

4

4

6

6

4

Look for an

admissible

arc.

8

8

1

2

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Breadth first search animation 20

7

6

5

4

Scan arc (4, 5)

LIST

1

2 4

5

3 6 9

7

8

311

22

5

3

4

4

6

6

4

Look for an

admissible

arc

8

8

1

2

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Breadth first search animation 21

7

6

5

4

Delete Node 4

LIST

1

2 4

5

3 6 9

7

8

311

22

5

3

4

4

6

6

4

Delete node 4

from LIST

8

8

4

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Breadth first search animation 23

8

7

6

5

4

Scan arc (6,7)

LIST

1

2 4

5

3 6 9

7

8

31

1

1

22

2 5

5

3

3

4

4

6

6

8

8

6

Scan arcs out

of node 6 one

at a time.

7

7

1

2

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Breadth first search animation 24

9

8

7

6

5

4

Scan arc (6,9)

LIST

1

2 4

5

3 6 9

7

8

311

22

5

3

4

6

6

8

8

6

7

7

9

9

Scan arcs out

of node 6 one

at a time.

1

2

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Breadth first search animation 25

9

8

7

6

5

4

Delete node 6

LIST

1

2 4

5

3 6 9

7

8

311

22

5

3

4

6

6

8

8

6

Delete node 6

from LIST

7

7

96

9

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Breadth first search animation 26

9

8

7

6

5

4

Select node 8

LIST

1

2 4

5

3 6 9

7

8

311

22

5

3

4

6

8

8

6

Select first

node on LIST

7

7

96

9

8

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Breadth first search animation 27

9

8

7

6

5

4

Delete node 8

LIST

1

2 4

5

3 6 9

7

8

311

22

5

3

4

6

8

8

6

Delete node 8

7

7

96

9

88

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Breadth first search animation 28

9

8

7

6

5

4

Select node 7

LIST

1

2 4

5

3 6 9

7

8

311

22

5

3

4

6

8

6

Select first

node on LIST

7

7

96

9

71

2 3

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Breadth first search animation 29

9

8

7

6

5

4

Scan arcs out of node 7

LIST

1

2 4

5

3 6 9

7

8

311

22

5

3

4

6

8

6

Scan arcs out

of node 7 one

at a time.

7

7

96

9

71

2 3

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Breadth first search animation 30

9

8

7

6

5

4

Delete node 7

LIST

1

2 4

5

3 6 9

7

8

311

22

5

3

4

6

8

6

Delete node 7

from LIST

7

7

96

9

77

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Breadth first search animation 31

9

8

7

6

5

4

Select node 9

LIST

1

2 4

5

3 6 9

7

8

311

22

5

3

4

6

8

6

Select the

first node on

LIST

7

96

9

9

1

2

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Breadth first search animation 32

9

8

7

6

5

4

Scan arcs out of node 9

LIST

1

2 4

5

3 6 9

7

8

311

22

5

3

4

6

8

6

Scan arcs out

of node 9,

one at a time

7

96

9

9

1

2

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Breadth first search animation 33

9

8

7

6

5

4

Delete node 9

LIST

1

2 4

5

3 6 9

7

8

311

22

5

3

4

6

8

6

Delete node 9

from LIST

7

96

9

99

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15.082J / 6.855J / ESD.78J Network OptimizationFall 2010

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