roy-floyd

///ROY-FLOYD
#include <iostream>
#include <fstream>
using namespace std;
int cost[100][100], n;
void citire()
{
    ifstream f("graf.in");
    f>>n;
    for (int i=1; i<=n; ++i)
        for(int j=1; j<=n; j++)
            f>>cost[i][j];
}
int main()
{
    citire();
    int i,j,k;
    for(k=1; k<=n; k++)
        for (int i=1; i<=n; ++i)
            for(int j=1; j<=n; j++)
                if(i!=j && i!=k && k!=j && cost[i][k]!=-1 && cost[k][j]!=-1 && cost[i][j]>cost[i][k]+cost[k][j])
                    cost[i][j]=cost[i][k]+cost[k][j];
    for (int i=1; i<=n; ++i)
    {
        for(int j=1; j<=n; j++)
            cout<<cost[i][j]<<" ";
        cout<<endl;
    }
}
/*graf.in
5
-1 -1 100 10 50
-1 -1 -1 10 -1
100 -1 -1 -1 10
10 10 -1 -1 10
50 -1 10 10 -1
*/