roy

#include <iostream.h>
#include <fstream.h>
int a[20][20];
int main (){
    int i,j,k,n,x,y;
    ifstream f("in.txt");
    f>>n;
    for(i=1;i<=n;i++)
        for(j=1;j<=n;j++)
            f>>a[i][j];
    f>>x>>y;
    for(k=1;k<=n;k++)
        for(i=1;i<=n;i++)
            for(j=1;j<=n;j++)
                if(a[i][j]==0 && i!=k && j!=k)
                    a[i][j]=a[i][k]*a[k][j];
    for(i=1;i<=n;i++){
        for(j=1;j<=n;j++)
            cout<<a[i][j]<<" ";
        cout<<endl;
    }
    cout<<a[x][y]<<" "<<a[y][x]<<endl;
    if(a[x][y]==1 && a[y][x]==1)
        cout<<"exista";
    else
        cout<<"nu exista";
    f.close();
}