Cod sursa(job #2829539)

Utilizator Mihai_EduardMihai Eduard Mihai_Eduard Data 8 ianuarie 2022 18:35:03
Problema Algoritmul Bellman-Ford Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.24 kb
#include <bits/stdc++.h>

using namespace std;

ifstream fin("bellmanford.in");
ofstream fout("bellmanford.out");
const int NMAX=50005;
const int inf=2e9;

int N, M, d[NMAX], viz[NMAX];
vector<pair<int,int>> g[NMAX];
queue<int> q;
bool inQueue[NMAX];

bool bellmanford(int sursa)
{
    for(int i=1;i<=N;i++)
        d[i]=inf;
    d[sursa]=0;

    q.push(sursa);
    inQueue[sursa]=true;
    int x;
    while(!q.empty())
    {
        x=q.front();
        q.pop();
        viz[x]++;
        inQueue[x]=false;

        if(viz[x]>=N)
            return false;

        for(auto next: g[x]){
            if(d[next.first]>d[x]+next.second){
                d[next.first]=d[x]+next.second;
                if(inQueue[next.first]==false){
                    inQueue[next.first]=true;
                    q.push(next.first);
                }
            }
        }
    }
    return true;
}

int main()
{
    fin>>N>>M;
    int x, y, z;
    for(int i=1;i<=M;i++){
        fin>>x>>y>>z;
        g[x].push_back({y,z});
    }

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

    fin.close();
    fout.close();
    return 0;
}