Cod sursa(job #2328001)

Utilizator filicriFilip Crisan filicri Data 25 ianuarie 2019 12:12:19
Problema Algoritmul Bellman-Ford Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.98 kb
#include <fstream>
#include <vector>
#include <queue>
#define nmax 50004
#define inf 100000000
#define f first
#define s second
using namespace std;
ifstream f("bellmanford.in");
ofstream g("bellmanford.out");
int n,m,dist[nmax],fr[nmax],ok,x,y,c;
vector <pair<int,int> > G[nmax];
queue <int> q;
int main()
{
    f>>n>>m;
    for (int i=1;i<=m;i++)
    {
        f>>x>>y>>c;
        G[x].push_back({y,c});
    }
    dist[1]=0;
    for (int i=2;i<=n;i++) dist[i]=inf;
    q.push(1);
    while (!q.empty() && !ok)
    {
        int node=q.front();
        q.pop();
        for (auto ne:G[node])
            if (fr[ne.f]<n && dist[node]+ne.s<dist[ne.f])
            {
                dist[ne.f]=dist[node]+ne.s;
                fr[ne.f]++;
                q.push(ne.f);
            }
            else if (fr[ne.f]>=n) ok=1;
    }
    if (ok==1) g<<"Ciclu negativ!";
    else for (int i=2;i<=n;i++) g<<dist[i]<<' ';
    f.close();
    g.close();
    return 0;
}