int uniquely(MGraph G)
{
  int nextAct = -1,cnt = 0;
  int former[MAXV] = {0};
  for(int i=0;i<MAXV;i++){
    for(int j=0;j<MAXV;j++){
      if(Edge[j][i]!=0)former[i]++;
    }
    if(former[i] == 0){
      nextAct = i;
      cnt++;
    }
  }

  for(int i=0;i<MAXV-1;i++){
    if(cnt!=1){
      return 0;
    }
    cnt--;
    for(int j=0;;<MAXV;j++){
      if(A[nextAct][j]!=0&&--former[j]==0){
        nextAct=j;
        cnt++;
      }
    }
  }
  return 1;
}