#include <bits/stdc++.h>

using namespace std;

#define int int64_t

const int mod = 998244353;
const int max_n = 500;
int d[max_n][max_n];

int32_t main() {
    ios_base::sync_with_stdio(false);
    cin.tie(0); cout.tie(0);
    int n, m;
    cin >> n >> m;
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++) {
            d[i][j] = 2e18;
        }
    }
    for (int i = 0; i < m; i++) {
        int a, b, c;
        cin >> a >> b >> c;
        d[a][b] = min(d[a][b], c);
        d[b][a] = min(d[b][a], c);
    }
    // dp(i)[a][b] = shortest path from a to b that uses only vertices [0..i) and a, b
    for (int i = 0; i < n; i++) {
        for (int a = 0; a < n; a++) {
            for (int b = 0; b < n; b++) {
                d[a][b] = min(d[a][b], d[a][i] + d[i][b]);
            }
        }
    }
}