Cod sursa(job #2375418)

Utilizator TudorFinaruTudor Cristian Finaru TudorFinaru Data 8 martie 2019 09:10:07
Problema Algoritmul Bellman-Ford Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.07 kb
#include <fstream>
#include<vector>
#include<queue>

using namespace std;

ifstream f("bellmanford.in");
ofstream g("bellmanford.out");

int n,m,cost[50003],viz[50003];
const int INF=0x3f3f3f3f;
vector<pair<int, int> >v[50003];

queue<int>q;

void bell_ford()
{
    int i, nod;
    for(i=2;i<=n;i++) cost[i]=INF;
    q.push(1);
    while(!q.empty())
    {
        nod=q.front();
        q.pop();
        viz[nod]++;
        if(viz[nod]>n) {g<<"Ciclu negativ!"<<'\n'; return;}
        vector<pair<int, int> >::iterator it;
        for(it=v[nod].begin();it!=v[nod].end();++it)
        {
            int c=it->second; int to=it->first;
            if(cost[nod]+c<cost[to])
            {
                cost[to]=cost[nod]+c;
                q.push(to);
            }
        }
    }
    for(i=2;i<=n;i++) g<<cost[i]<<' ';
    g<<'\n';
}

int main()
{
    int x,y,c;
    f>>n>>m;
    int i;
    for(i=1;i<=m;i++)
    {
        f>>x>>y>>c;
        v[x].push_back(make_pair(y,c));
    }
    bell_ford();
    f.close();
    g.close();
    return 0;
}