Graph/test/aizu_grl_1_c_floyd_warshall.test.cpp

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• Last update: 2025-06-11 15:37:14+07:00
• Problem: https://onlinejudge.u-aizu.ac.jp/courses/library/5/GRL/1/GRL_1_C

Depends on

• Graph/Shortest_path/Floyd_warshall.h
• template.h

Code

#define PROBLEM "https://onlinejudge.u-aizu.ac.jp/courses/library/5/GRL/1/GRL_1_C"

#include "../../template.h"
#include "../Shortest_path/Floyd_warshall.h"

void solve() {
    int n, m; cin >> n >> m;
    vector<vector<ll>> d(n+1, vector<ll>(n+1, 1e18));
    vector<vector<int>> trace(n+1, vector<int>(n+1));
    for (int i = 1; i <= n; i++) {
        d[i][i] = 0;
    }
    for (int i = 0; i < m; i++) {
        ll u, v, w; cin >> u >> v >> w;
        d[u+1][v+1] = min(d[u+1][v+1], w);
    }
    floyd_warshall(n, d, trace);
    for (int i = 1; i <= n; i++) {
        if (d[i][i] < 0) {
            cout << "NEGATIVE CYCLE\n";
            return;
        }
    }
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++) {
            if (d[i+1][j+1] == 1e18) {
                cout << "INF";
            } else {
                cout << d[i+1][j+1];
            }
            cout << (j == n - 1 ? '\n' : ' ');
        }
    }
}

#line 1 "Graph/test/aizu_grl_1_c_floyd_warshall.test.cpp"
#define PROBLEM "https://onlinejudge.u-aizu.ac.jp/courses/library/5/GRL/1/GRL_1_C"

#line 2 "template.h"

#include <bits/stdc++.h>
using namespace std;
 
#define ll long long
#define MOD (ll)(1e9+7)
#define all(x) (x).begin(),(x).end()
#define unique(x) x.erase(unique(all(x)), x.end())
#define INF32 ((1ull<<31)-1)
#define INF64 ((1ull<<63)-1)
#define inf (ll)1e18

#define vi vector<int>
#define pii pair<int, int>
#define pll pair<ll, ll>
#define fi first
#define se second

const int mod = 998244353;

void solve();

int main(){
    ios_base::sync_with_stdio(false);cin.tie(NULL);
    // cin.exceptions(cin.failbit);
    // int t; cin >> t;
    // while(t--)
        solve();
    cerr << "\nTime run: " << 1000 * clock() / CLOCKS_PER_SEC << "ms" << '\n';
    return 0;
}
#line 2 "Graph/Shortest_path/Floyd_warshall.h"

void initTrace(int n, vector<vector<int>> &trace) {
    for (int u = 1; u <= n; ++u) {
        for (int v = 1; v <= n; ++v) {
            trace[u][v] = u;
        }
    }
}

void floyd_warshall(int n, vector<vector<ll>> &dist, vector<vector<int>> &trace) {
    initTrace(n, trace);
    for (int k = 1; k <= n; ++k) {
        for (int u = 1; u <= n; ++u) {
            for (int v = 1; v <= n; ++v) {
                if (dist[u][k] != 1e18 && dist[k][v] != 1e18 && dist[u][v] > dist[u][k] + dist[k][v]) {
                    dist[u][v] = dist[u][k] + dist[k][v];
                    trace[u][v] = trace[k][v];
                }
            }
        }
    }
}
#line 5 "Graph/test/aizu_grl_1_c_floyd_warshall.test.cpp"

void solve() {
    int n, m; cin >> n >> m;
    vector<vector<ll>> d(n+1, vector<ll>(n+1, 1e18));
    vector<vector<int>> trace(n+1, vector<int>(n+1));
    for (int i = 1; i <= n; i++) {
        d[i][i] = 0;
    }
    for (int i = 0; i < m; i++) {
        ll u, v, w; cin >> u >> v >> w;
        d[u+1][v+1] = min(d[u+1][v+1], w);
    }
    floyd_warshall(n, d, trace);
    for (int i = 1; i <= n; i++) {
        if (d[i][i] < 0) {
            cout << "NEGATIVE CYCLE\n";
            return;
        }
    }
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++) {
            if (d[i+1][j+1] == 1e18) {
                cout << "INF";
            } else {
                cout << d[i+1][j+1];
            }
            cout << (j == n - 1 ? '\n' : ' ');
        }
    }
}

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