Cod sursa(job #2941272)

Utilizator moise_alexandruMoise Alexandru moise_alexandru Data 17 noiembrie 2022 16:08:10
Problema Algoritmul Bellman-Ford Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.31 kb
#include <iostream>
#include <fstream>
#include <vector>
#include <bitset>
#include <queue>
using namespace std;
ifstream in("bellmanford.in");
ofstream out("bellmanford.out");
const int maxn = 50005;
vector <pair <int, int> > v[maxn];
bitset <maxn> incoada;
int dist[maxn];
int fr[maxn];
int main()
{
    int n, m;
    in >> n >> m;
    for(int i = 1; i <= m; i++)
    {
        int x, y, cost;
        in >> x >> y >> cost;
        v[x].push_back(make_pair(y, cost));
    }
    for(int i = 2; i <= n; i++)
        dist[i] = (1 << 30);
    queue <int> q;
    q.push(1);
    while(!q.empty())
    {
        int nod = q.front();
        q.pop();
        incoada[nod] = 0;
        fr[nod]++;
        if(fr[nod] == n + 1) /// am gasit un ciclu negativ
        {
            out << "Ciclu negativ!" << "\n";
            return 0;
        }
        for(auto it : v[nod])
        {
            if(dist[it.first] > dist[nod] + it.second)
            {
                dist[it.first] = dist[nod] + it.second;
                if(!incoada[it.first])
                {
                    q.push(it.first);
                    incoada[it.first] = 1;
                }
            }
        }
    }
    for(int i = 2; i <= n; i++)
        out << dist[i] << " ";
    out << "\n";
    return 0;
}