Floyd_Warshall.cpp

#include <bits/stdc++.h>
using namespace std;

#define pb push_back
#define lli long long int
#define MAXN 10000
#define INF 999999

int n , m , a , b , c ;
int dist [MAXN][MAXN] ;

void floyd_warshall ()
{
    for (int k = 0 ; k < n ; k++)
    {
        for (int i = 0 ; i < n ; i++)
        {
            for (int j = 0 ; j < n ; j++)
            {
                dist[i][j] = min(dist[i][j] , dist[i][k] + dist[k][j]) ;
            }
        }
    }
}
void initialize ()
{
    for (int i = 0 ; i < n ; i++)
    {
        for (int j = 0 ; j < n ; j++)
        {
            if (i == j)
            {
                dist[i][j] = 0 ;
            }
            else
            {
                dist[i][j] = INF ;
            }
            
        }
    }
}
int main()
{   
    cin >> n >> m ;

    initialize () ;

    for (int i = 0 ; i < m ; i++)
    {
        cin >> a >> b >> c ;
        dist [a][b] = min (dist[a][b] , c) ;
        dist [b][a] = min (dist[b][a] , c) ;
    }

    floyd_warshall () ;
    
    return 0;
}