Cod sursa(job #3373630)

Utilizator Laura721Laura Kudor Laura721 Data 7 noiembrie 2026 13:27:54
Problema Algoritmul Bellman-Ford Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.23 kb
#include <iostream>
#include <fstream>
#include <vector>
#include <queue>
using namespace std;
ifstream fin("bellmanford.in");
ofstream fout("bellmanford.out");
const int nmax=50000;
const int oo=1e9;
vector <pair<int,int>> g[nmax+5];
queue <int> q;
int n,m,d[nmax+5],nrq[nmax+5];
bool inq[nmax+5];
void read(){
    fin>>n>>m;
    for(int i=1;i<=m;++i){
        int x,y,c;
        fin>>x>>y>>c;
        g[x].push_back(make_pair(y,c));
    }
}
void bellmanford(){
    for(int i=2;i<=n;++i)
        d[i]=oo;
    q.push(1);
    int ok=1;
    while(!q.empty() && ok){
        int i=q.front();
        q.pop();
        inq[i]=false;
        for(auto it:g[i]){
            int vecin=it.first,cost=it.second;
            if(d[vecin]>d[i]+cost){
                d[vecin]=d[i]+cost;
                if(!inq[vecin]){
                    q.push(vecin);
                    inq[vecin]=true;
                }
                nrq[vecin]++;
                if(nrq[vecin]>=n)
                    ok=0;
            }
        }
    }
    if(ok==0){
        fout<<"Ciclu negativ!";
        return;
    }
    for(int i=2;i<=n;++i)
        fout<<d[i]<<" ";

}
int main()
{
    read();
    bellmanford();
    return 0;
}