Cod sursa(job #1870826)

Utilizator vancea.catalincatalin vancea.catalin Data 6 februarie 2017 22:36:34
Problema Algoritmul Bellman-Ford Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.09 kb
#include<iostream>
#include<fstream>
#include<vector>
#include<bitset>
#include<queue>
#define DN 50100
#define inf 1000000000
using namespace std;
fstream fin("bellmanford.in",ios::in),fout("bellmanford.out",ios::out);
vector<pair<int,int> > v[DN];
bitset<DN> bit;
queue<int> q;
int n,m,d[DN],nr[DN];

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