Cod sursa(job #2140855)

Utilizator stefii_predaStefania Preda stefii_preda Data 23 februarie 2018 22:24:00
Problema Algoritmul Bellman-Ford Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.39 kb
#include <fstream>
#include <vector>
#include <queue>

using namespace std;

ifstream in ("bellmanford.in");
ofstream out ("bellmanford.out");
const int N = 50005;
const int INF = 2000000000;

struct muchie
{
    int nod, cost;
};
vector <muchie> g[N];
queue <int> q;
int d[N], nrviz[N];
bool incoada[N];

int main()
{
    int n, m, a, b, c, i;
    in >> n >> m;
    for(i = 1; i <= m; i++)
    {
        in >> a >> b >> c;
        g[a].push_back({b, c});
    }
    q.push(1);
    incoada[1] = true;
    nrviz[1] = 1;
    for(i = 2; i <= n; i++)
        d[i] = INF;
    int node;
    while(!q.empty())
    {
        node = q.front();
        q.pop();
        incoada[node] = false;
        for(i = 0; i < g[node].size(); ++i)
        {
            if(d[g[node][i].nod] > d[node] + g[node][i].cost)
            {
                d[g[node][i].nod] = d[node] + g[node][i].cost;
                if(incoada[g[node][i].nod] == false)
                {
                    q.push(g[node][i].nod);
                    incoada[g[node][i].nod] = true;
                }
                nrviz[g[node][i].nod] ++;
                if(nrviz[g[node][i].nod] > n)
                {
                    out << "Ciclu negativ!";
                    return 0;
                }

            }
        }
    }
    for(i = 2; i <= n; i++)
        out << d[i] << " ";

    return 0;
}