// 教学模板：有向图，无负环。输入 n m，随后 m 行 u v w。
// 输出 n 行最短距离矩阵，不可达写 INF。这个输出约定为教学自拟。
// 建议教学数据 n<=500、|w|<=10^9，有限路长和候选之和远小于 INF。
#include <algorithm>
#include <iostream>
#include <vector>
using namespace std;
using ll = long long;
const ll INF = 1LL << 60;

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    int n, m;
    cin >> n >> m;
    vector<vector<ll>> d(n + 1, vector<ll>(n + 1, INF));
    for (int i = 1; i <= n; ++i) d[i][i] = 0;
    for (int t = 0; t < m; ++t) {
        int u, v;
        ll w;
        cin >> u >> v >> w;
        d[u][v] = min(d[u][v], w);
    }
    for (int k = 1; k <= n; ++k)
        for (int i = 1; i <= n; ++i)
            for (int j = 1; j <= n; ++j) {
                if (d[i][k] == INF || d[k][j] == INF) continue;
                ll nd = d[i][k] + d[k][j];
                d[i][j] = min(d[i][j], nd);
            }
    for (int i = 1; i <= n; ++i) {
        for (int j = 1; j <= n; ++j) {
            if (j > 1) cout << ' ';
            if (d[i][j] == INF) cout << "INF";
            else cout << d[i][j];
        }
        cout << '\n';
    }
}