fork(5) download
copy 
  1. #include<stdio.h>
  2. #include<iostream>
  3. #include<queue>
  4.  
  5. using namespace std;
  6.  
  7. #define MAX 100
  8. #define initial  1
  9. #define visited  2
  10.  
  11. int arr[MAX][MAX],n,topo_order[MAX],indeg[MAX]={0};
  12.  
  13. queue<int> myque;
  14.  
  15. void createGraph()
  16. {
  17.     printf("enter the number of edges : ");
  18.     scanf("%d",&n);
  19.     int i,src,dest,edge=n*(n-1);
  20.     for(i=0;i<edge;i++)
  21.     {
  22.         printf("enter the source and destination or(-1,-1) to  quit : ");
  23.         scanf("%d %d",&src,&dest);
  24.         if(src==-1 && dest==-1)
  25.             break;
  26.         else if(src>=n||src<0||dest>=n||dest<0)
  27.         {
  28.             printf("invalid input\n");
  29.             i--;
  30.         }
  31.         else
  32.         {
  33.             arr[src][dest]=1;
  34.             indeg[dest]++;
  35.         }
  36.     }
  37. }
  38.  
  39. void toposort()
  40. {
  41.     int i,count=0,v,j=0;
  42.     for(i=0;i<n;i++)
  43.         if(indeg[i]==0)
  44.             myque.push(i);
  45.     while(!myque.empty() && count<n)
  46.     {
  47.         v=myque.front();
  48.         topo_order[j]=v;
  49.         j++;
  50.         myque.pop();
  51.         for(i=0;i<n;i++)
  52.         {
  53.             if(arr[v][i]==1)
  54.             {
  55.                 arr[v][i]=0;
  56.                 indeg[i]--;
  57.                 if(indeg[i]==0)
  58.                     myque.push(i);
  59.             }
  60.         }
  61.     }
  62.     for(i=0;i<n;i++)
  63.         printf("%d ",topo_order[i]);
  64. }
  65.  
  66.  
  67. int main()
  68. {
  69.     createGraph();
  70.     toposort();
  71.     return 0;
  72. }
  73.  
Success #stdin #stdout 0s 3476KB
comments (?)
stdin
copy 
Standard input is empty
stdout
copy 
enter the number of edges :
https://ideone.com/Q3J0nh
language:
C++ (gcc 8.3)
created:
9 years ago
visibility:
secret

Share or Embed source code

Discover > Sphere Engine API

The brand new service which powers Ideone!

Discover > IDE Widget

Widget for compiling and running the source code in a web browser!