Cod sursa(job #1857166)

Utilizator vladbatalanBatalan Vlad vladbatalan Data 25 ianuarie 2017 21:23:11
Problema Algoritmul Bellman-Ford Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.47 kb
#include <bits/stdc++.h>
#define MAXN 50010
using namespace std;

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

vector<pair<int, int> > v[MAXN];
queue<int> coada;
bitset<MAXN> in_coada;
int dist[MAXN], cnt_in_coada[MAXN];
int n,m,x,y,w;

int main()
{
    fin>>n>>m;
    for(int i=1;i<=m;i++)
    {
        fin>>x>>y>>w;
        v[x].push_back(make_pair(y,w));
    }
    for(int i=1;i<=n;i++)
        dist[i]=MAXN;
    int cost, nod;
    dist[1]=0;
    coada.push(1);
    in_coada[1] = 1;
    bool negative;
    while(!coada.empty() && !negative)
    {
        int top = coada.front();
        coada.pop();
        in_coada[top] = 0;
        for(auto it:v[top])
        {
            nod = it.first;
            cost = it.second;
            if(dist[nod] > dist[top] + cost)
            {
                dist[nod] = dist[top] + cost;
                if(!in_coada[nod])
                {
                    if(cnt_in_coada[nod] > n)
                    {
                        negative = 1;
                        fout<<"Ciclu negativ!\n";
                        return 0;
                    }
                    else
                    {
                        coada.push(nod);
                        in_coada[nod] = 1;
                        cnt_in_coada[nod]++;
                    }
                }
            }

        }
    }

    for(int i=2;i<=n;i++)
        fout<<dist[i]<<" ";
    return 0;
}