Cod sursa(job #2138401)

Utilizator sulzandreiandrei sulzandrei Data 21 februarie 2018 16:56:27
Problema Algoritmul Bellman-Ford Scor 10
Compilator cpp Status done
Runda Arhiva educationala Marime 1.23 kb
#include <iostream>
#include <fstream>
#include <vector>
#include <queue>
using namespace std;
ifstream in("bellmanford.in");
ofstream out("bellmanford.out");
#define maxm  250010
#define maxn  50010
int d[maxn];

struct edge
{
    int a,b,c;
}e[maxm];
vector<edge> v[maxn];
bool visited[maxn]{false};
int main()
{
   int n,m;
   queue<int> que;
   in >> n >> m;
   for(int i = 0  ;i < m ; i++)
   {
       in >> e[i].a>>e[i].b>>e[i].c;
       v[e[i].a].push_back(e[i]);
   }
   for(int i = 1 ; i<= n  ; i++)
        d[i] = 1<<30;
    d[1] =0;

    que.push(1);
    int nod;
    int counter = 0;
    while(!que.empty() && counter <= n*m)
    {
        counter++;
        nod = que.front(); que.pop();
        visited[nod] = true;
        for(edge nei:v[nod])
            if(d[nod]+nei.c < d[nei.b])
            {
                if(!visited[nei.b])
                {
                    d[nei.b] = d[nod]+nei.c;
                    que.push(nei.b);
                }

            }

    }
    for(edge nou:e)
    {
        if (d[nou.a] + nou.c < d[nou.b])
        {
            out<<"Ciclu negativ!";
            return 0;
        }
    }
    for(int i = 2 ; i <= n ; i++)
        out<<d[i]<<" ";
}