Cod sursa(job #2166850)

Utilizator caprariuapCaprariu Alin-Paul caprariuap Data 13 martie 2018 19:12:32
Problema Algoritmul Bellman-Ford Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.24 kb
#include <fstream>
#include <cstring>
#include <algorithm>
#include <vector>
#include <queue>
#include <set>

using namespace std;

ifstream fin("bellmanford.in");
ofstream fout("bellmanford.out");

queue <int> q;
vector <int> v[50010],cost[50010];
int n,m,i,inQ[50010],d[50010],nre[50010];

int main()
{
    fin >> n >> m;
    for (i=1; i<=m; i++)
    {
        int a,b,c;
        fin >> a >> b >> c;
        v[a].push_back(b);
        cost[a].push_back(c);
    }
    for (i=2; i<=n; i++)
        d[i]=250000010;
    q.push(1);
    nre[1]=1;
    inQ[1]=1;
    while (!q.empty())
    {
        int x=q.front();
        q.pop();
        inQ[x]=0;
        for (i=0; i<v[x].size(); i++)
            if (d[x]+cost[x][i]<d[v[x][i]])
            {
                d[v[x][i]]=d[x]+cost[x][i];
                if (inQ[v[x][i]]==0)
                {
                    q.push(v[x][i]);
                    inQ[v[x][i]]=1;
                }
                nre[v[x][i]]++;
                if (nre[v[x][i]]>n)
                {
                    fout << "Ciclu negativ!\n";
                    return 0;
                }
            }
    }
    for (i=2; i<=n; i++)
        fout << d[i] << ' ';
    fout << '\n';
}