Cod sursa(job #3286115)

Utilizator adimiclaus15Miclaus Adrian Stefan adimiclaus15 Data 13 martie 2025 18:52:21
Problema Algoritmul Bellman-Ford Scor 35
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.26 kb
#include <bits/stdc++.h>

using namespace std;

ifstream f("bellmanford.in");
ofstream g("bellmanford.out");

const int NMAX = 5e4;
const int INF = 1e9;
vector<pair<int, int>> G[NMAX + 1];
int d[NMAX + 1];
int vis[NMAX + 1];
int cnt[NMAX + 1];
int n, m;

void bellman_ford(int src) {
    queue<int> q;
    for(int i = 1; i <= n; i++) {
        d[i] = INF;
    }
    d[src] = 0;
    vis[src] = 1;
    q.push(src);
    while(!q.empty()) {
        int node = q.front();
        q.pop();
        vis[node] = 0;
        for(auto next : G[node]) {
            int vecin = next.first;
            int cost = next.second;
            if(d[vecin] > d[node] + cost) {
                d[vecin] = d[node] + cost;
                if(vis[vecin] == 0) {
                    q.push(vecin);
                    vis[vecin] = 1;
                    cnt[vecin]++;
                    if(cnt[vecin] > n) {
                        g << "Ciclu negativ!";
                        return ;
                    }
                }
            }
        }
    }
}

int main() {
    
    f >> n >> m;
    for(int i = 1; i <= m; i++) {
        int a, b, c;
        f >> a >> b >> c;
        G[a].push_back({b, c});
    }
    bellman_ford(1);
    for(int i = 2; i <= n; i++) {
        g << d[i] << ' ';
    }
    return 0;
}