Cod sursa(job #2551374)

Utilizator DavidDragulinDragulin David DavidDragulin Data 19 februarie 2020 19:45:45
Problema Algoritmul Bellman-Ford Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.18 kb
#include <bits/stdc++.h>
#define pb push_back

using namespace std;
ifstream fin("bellmanford.in");
ofstream fout("bellmanford.out");
typedef pair<int,int> Pair;
const int N=50009,inf=INT_MAX;
int n,m,d[N],prez[N];
vector <Pair> v[N];
priority_queue <Pair, vector<Pair> ,greater <Pair> > q;
int main()
{
    fin.sync_with_stdio(false);
    fin>>n>>m;
    for(int i=1;i<=m;i++)
    {
        int x,y,c;
        fin>>x>>y>>c;
        v[x].pb({y,c});
    }
    q.push({0,1});
    for(int i=1;i<=n;i++)
        d[i]=inf;
    d[1]=0;
    while(!q.empty())
    {
        int nod=q.top().second;
        q.pop();
        if(prez[nod]<n)
        {
            prez[nod]++;
            for(auto it:v[nod])
            {
                if(d[nod]+it.second<d[it.first])
                {
                    d[it.first]=d[nod]+it.second;
                    q.push({d[it.first],it.first});
                }
            }
        }
        else
        {
            fout<<"Ciclu negativ!";
            return 0;
        }
    }
    for(int i=2;i<=n;i++)
        if(d[i]!=inf)
            fout<<d[i]<<" ";
        else
            fout<<0<<" ";
    return 0;
}