Cod sursa(job #2304406)

Utilizator canmihaiCancescu Mihai canmihai Data 17 decembrie 2018 23:26:29
Problema Algoritmul Bellman-Ford Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.2 kb
#include <iostream>
#include <fstream>
#include <vector>
#include <bitset>
#include <queue>
#include <climits>
#define dim 50010
using namespace std;
ifstream fin("bellmanford.in");
ofstream fout("bellmanford.out");
int n,m,x,y,z,d[dim]={INT_MAX},n2[dim];
vector<pair<int,int>>v2[dim];
queue <int> q;
bitset <dim> v;
int main(){
    fin>>n>>m;
    for(int i=1;i<=m;i++){
        fin>>x>>y>>z;
        v2[x].push_back(make_pair(y,z));

    }
    q.push(1);
    v[1]=1;
    d[1]=0;
    for(int i=2;i<=n;i++)
        d[i]=1000000000;//de ce nu mergea de la inceput??
    while(!q.empty()){
        x=q.front();
        q.pop();
        v[x]=0;
        for(int i=0;i<v2[x].size();i++){
            y=v2[x][i].first;
            if(d[y]>d[x]+v2[x][i].second){
                d[y]=d[x]+v2[x][i].second;
                if(!v[y]){
                    n2[y]++;
                    if(n2[y]==n){
                        fout<<"Ciclu negativ!";
                        return 0;
                    }
                    q.push(y);
                    v[y]=1;
                }

            }
        }

    }

    for (int i=2;i<=n;i++)
        fout<<d[i]<<" ";


    return 0;
}