280 – Vertex

I used floyd to get the transitive closure instead of dfs from each node

#include <istream>
#include <stdio.h>

using namespace std;

int main()
{
    int n;
    while(scanf("%d",&n)&&n)
    {
        bool matrix[n][n];
        for (int i=0;i<n;i++)
            for (int j=0;j<n;j++)
                matrix[i][j]=false;
        int x ;
        while(scanf("%d",&x)&&x)
        {
            int y;
            while(scanf("%d",&y)&&y)
            {
                matrix[x-1][y-1] = true;
            }
        }
        for (int k=0;k<n;k++)
             for (int i=0;i<n;i++)
                 for (int j=0;j<n;j++)
                     if(matrix[i][k]&&matrix[k][j])
                         matrix[i][j]=true;
        int z;
        scanf("%d",&z);
        while(z-->0)
        {
            int w;
            scanf("%d",&w);
            int count=0;
            for (int i=0;i<n;i++)
                if(matrix[w-1][i]== false)
                    count++;
            printf("%d",count);
            for (int i=0;i<n;i++)
                if(matrix[w-1][i] == false)
                    printf(" %d",(i+1));
            printf("\n");
        }

    }

    return 0;
}