Cod sursa(job #2692294)

Utilizator Razvank206Dumitriu Razvan Razvank206 Data 2 ianuarie 2021 10:09:59
Problema Algoritmul Bellman-Ford Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.27 kb

#include <bits/stdc++.h>
#define inf 1000000000
#define dim 50005
using namespace std;
string numeproblema="bellmanford";
ifstream fin(numeproblema+".in");
ofstream fout(numeproblema+".out");
int d[dim],n,i,x,y,z,nr[dim],m;
vector <pair<int,int> > L[dim];
deque <int> q;
bitset <dim> fr;
void bf(int nod)
{
    int cost;
    fr[nod]=1; /// se face oricum 0
    d[1]=0;
    q.push_back(nod);
    while(!q.empty())
    {
        nod=q.front();
        nr[nod]++;
        if(nr[nod]>n)
        {
            fout<<"Ciclu negativ!";
            return;
        }
        q.pop_front();
        fr[nod]=0;
        for(int i=0; i<L[nod].size(); i++)
        {
            if(d[nod]+L[nod][i].second<d[L[nod][i].first])
            {
                d[L[nod][i].first]=d[nod]+L[nod][i].second;
                if(fr[L[nod][i].first]==0)  ///daca e in coada
                {
                    fr[L[nod][i].first]=1;
                    q.push_back(L[nod][i].first);
                }
            }
        }
    }
    for(int i=2; i<=n; i++)
        fout<<d[i]<<" ";

}
int main()
{
    fin>>n>>m;
    for(i=1; i<=m; i++)
    {
        fin>>x>>y>>z;
        L[x].push_back({y,z});
    }
    for(i=1; i<=n; i++)
        d[i]=inf;
    bf(1);

}