FilesExpand file tree

 master

/

DFS.java

Copy path

Blame

More file actions

Blame

More file actions

Latest commit

 

History

History

History

63 lines (55 loc) · 1.72 KB

 master

/

DFS.java

Copy path

Top

File metadata and controls

• Code
• Blame

63 lines (55 loc) · 1.72 KB

Raw

Copy raw file

Download raw file

Open symbols panel

Edit and raw actions

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

32

33

34

35

36

37

38

39

40

41

42

43

44

45

46

47

48

49

50

51

52

53

54

55

56

57

58

59

60

61

62

63

import java.util.*;

/**

* Implementation of a Depth First Search

*

* @author Unknown

*

*/

public class DFS{

/**

* Implementation in code of a DFS

*

* @param a structure to be DFS'ed

* @param vertices The vertices

* @param source The source

*/

public static void dfsImplement(byte [][] a,int vertices,int source){ //passing adjacency matrix and no of vertices

byte []b=new byte[vertices]; //flag container containing status of each vertices

Arrays.fill(b,(byte)-1); //status initialization

/* code status

-1 = ready

0 = waiting

1 = processed */

Stack st=new Stack(vertices); //operational stack

st.push(source); //assigning source

while(!st.isEmpty()){

b[st.peek()]=(byte)0; //assigning waiting status

System.out.println(st.peek());

int pop=st.pop();

b[pop]=(byte)1; //assigning processed status

for(int i=0;i<vertices;i++){

if(a[pop][i]!=0 && b[i]!=(byte)0 && b[i]!=(byte)1 ){

st.push(i);

b[i]=(byte)0; //assigning waiting status

}}}

}

/**

* The main method

*

* @param args Command line arguments

*/

public static void main(String args[]){

Scanner in=new Scanner(System.in);

int vertices=in.nextInt(),source=in.nextInt();

byte [][]a=new byte [vertices][vertices];

//initially all elements of a are initialized with value zero

for(int i=0;i<vertices;i++){

int size =in.nextInt();

for(int j=0;j<size;j++){

a[i][in.nextInt()]=1; //taking adjacency entries by assigning 1

}

}

dfsImplement(a,vertices,source); //function call

in.close();

}

}