Cod sursa(job #3325410)

Utilizator CVCiprianConstandache Vlad-Ciprian CVCiprian Data 25 noiembrie 2025 13:29:40
Problema Algoritmul Bellman-Ford Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.55 kb
#include <bits/stdc++.h>
using namespace std;

#define INF 2000000000

ifstream fin("bellmanford.in");
ofstream fout("bellmanford.out");

int n, m;
int d[50001];
int cnt[50001];
bool in_queue[50001];
vector<pair<int,int>> v[50001];
queue<int> q;

bool bellmanford(int s)
{
    for(int i = 1; i <= n; i++)
    {
        d[i] = INF;
        cnt[i] = 0;
        in_queue[i] = false;
    }

    d[s] = 0;
    q.push(s);
    in_queue[s] = true;

    while(!q.empty())
    {
        int nod = q.front();
        q.pop();
        in_queue[nod] = false;

        cnt[nod]++;
        if(cnt[nod] >= n)
        {
            return true;
        }

        for(auto &e : v[nod])
        {
            int vecin = e.first;
            int cost = e.second;

            if(d[nod] != INF && d[nod] + cost < d[vecin])
            {
                d[vecin] = d[nod] + cost;
                if(!in_queue[vecin])
                {
                    q.push(vecin);
                    in_queue[vecin] = true;
                }
            }
        }
    }
    return false;
}

int main()
{
    fin >> n >> m;

    int x, y, z;
    for(int i = 1; i <= m; i++)
    {
        fin >> x >> y >> z;
        v[x].push_back({y, z});
    }

    if (bellmanford(1))
    {
        fout << "Ciclu negativ!";
    }
    else
    {
        for(int i = 2; i <= n; i++)
        {
            if(d[i] == INF)
                fout << 0 << " ";
            else
                fout << d[i] << " ";
        }
    }

    return 0;
}