# C Program to implement Warshall’s Algorithm

Levels of difficulty: / perform operation:

Warshall’s algorithm enables to compute the transitive closure of the adjacency matrix of any digraph.

### C Program

```#include<stdio.h>
#include<conio.h>
#include<math.h>
int max(int,int);
void warshal(int p[10][10],int n) {
int i,j,k;
for (k=1;k<=n;k++)
for (i=1;i<=n;i++)
for (j=1;j<=n;j++)
p[i][j]=max(p[i][j],p[i][k]&&p[k][j]);
}
int max(int a,int b) {
;
if(a>b)
return(a); else
return(b);
}
void main() {
int p[10][10]= {
0
}
,n,e,u,v,i,j;
clrscr();
printf("\n Enter the number of vertices:");
scanf("%d",&n);
printf("\n Enter the number of edges:");
scanf("%d",&e);
for (i=1;i<=e;i++) {
printf("\n Enter the end vertices of edge %d:",i);
scanf("%d%d",&u,&v);
p[u][v]=1;
}
printf("\n Matrix of input data: \n");
for (i=1;i<=n;i++) {
for (j=1;j<=n;j++)
printf("%d\t",p[i][j]);
printf("\n");
}
warshal(p,n);
printf("\n Transitive closure: \n");
for (i=1;i<=n;i++) {
for (j=1;j<=n;j++)
printf("%d\t",p[i][j]);
printf("\n");
}
getch();
}
```