10_topology_source.c

//Topological sorting using source removal
#include<stdio.h>
#include<stdlib.h>
#define MAX 100

void main() {
    int graph[MAX][MAX], flag[MAX], indeg[MAX], n, i, j, k, count=0;
    printf("\nEnter the number of nodes in the graph:\n");
    scanf("%d", &n);
    printf("\nEnter the adjacency matrix:\n");
    for(i=0; i<n; i++){
        for(j=0; j<n; j++){
            scanf("%d", &graph[i][j]);
        }
        flag[i] = 0;
        indeg[i] = 0;
    }

    for(i=0; i<n; i++) {
        for(j=0; j<n; j++) {
            indeg[i] += graph[j][i]; 
        }
    }
    
    printf("\nThe topological oreder is:\n");
    while(count < n) {
        int pos;
        for(k=0; k<n; k++) {
            if(indeg[k] == 0 && flag[k] == 0){
                printf(" --> %c", k+65);
                flag[k] = 1;
                pos = k;
                break;
            }
        }

        for(i=0; i<n; i++) {
            if(graph[pos][i] == 1)
                indeg[i]--;
        }

        count++;
    } 
}