Cod sursa(job #2505256)

Utilizator lucianul31Moisii Lucian lucianul31 Data 6 decembrie 2019 16:32:23
Problema Algoritmul Bellman-Ford Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.28 kb
#include<bits/stdc++.h>

using namespace std;

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

const int NMAX = 50005;
const int inf = 1e9;

struct muchie
{
    int node, cost;
};
int n,m,dist[NMAX],cot[NMAX];
muchie z;
bool ciclu;
vector < muchie > v[NMAX];
deque < int > q;

void BellmanFord(const int start_node)
{
    int nod,i;
    q.push_back(start_node);
    for(i = 1 ; i <= n ; i++)
        dist[i] = inf;
    dist[1] = 0;
    while(!q.empty())
    {
        nod = q.front();
        q.pop_front();
        for(i = 0 ; i < v[nod].size() && !ciclu; i++)
            if(dist[v[nod][i].node] > dist[nod] + v[nod][i].cost)
            {
                dist[v[nod][i].node] = dist[nod] + v[nod][i].cost;
                q.push_back(v[nod][i].node);
                cot[v[nod][i].node]++;
                if(cot[v[nod][i].node] > n)
                    ciclu = 1;
            }
    }
}

int main()
{
    int i, a, b, c;
    in>>n>>m;
    for(i=1; i<=m; i++)
    {
        in>>a>>b>>c;
        z.node=b;
        z.cost=c;
        v[a].push_back(z);
    }
    BellmanFord(1);
    if(ciclu)
        out<<"Ciclu negativ!"<<"\n";
    else
    {
        for(i = 2 ; i <= n ; i++)
            out<<dist[i]<<" ";
    }
    return 0;
}