Cod sursa(job #2803612)

Utilizator luciabianca2405Tudorache Lucia Bianca luciabianca2405 Data 20 noiembrie 2021 11:34:03
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");
vector<pair<int,int>>g[50001];
int D[50001],oo=2000000,Viz[50001];
vector<bool>Use;
int N;
queue<int>q;
void read()
{
    int m,x,y,c;
    fin>>N>>m;
    Use=vector<bool>(N+1);
    for(int i=1; i<=m; i++)
    {
        fin>>x>>y>>c;
        g[x].push_back(make_pair(y,c));
    }
}
bool bellmanford()
{
    int Nod;
    for(int i=2; i<=N; i++)
        D[i]=oo;
    Use[1]=true;
    q.push(1);
    while(!q.empty())
    {
        Nod=q.front();
        q.pop();
        Viz[Nod]++;
        if(Viz[Nod]>=N)
            return false;
        Use[Nod]=false;
        for(int i=0; i<g[Nod].size(); i++)
        {
            int Vecin=g[Nod][i].first,Cost=g[Nod][i].second;
            if(D[Nod]+Cost<D[Vecin])
            {
                D[Vecin]=D[Nod]+Cost;
                if(!Use[Vecin])
                    Use[Vecin]=true,q.push(Vecin);
            }
        }
    }
    return true;
}
void afisare()
{
    if(bellmanford())
        for(int i=2; i<=N; i++)
            fout<<D[i]<<' ';
    else
        fout<<"Ciclu negativ!";
}
int main()
{
    read();
    bellmanford();
    afisare();
}