Cod sursa(job #3144218)

Utilizator Maftei_TudorMaftei Tudor Maftei_Tudor Data 6 august 2023 13:44:33
Problema Algoritmul Bellman-Ford Scor 20
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.28 kb
#include <fstream>
#include <vector>
#include <queue>

#define pb push_back

using namespace std;
ifstream in("bellmanford.in");
ofstream out("bellmanford.out");
const int inf = 2e9;

int n, m, fr[50005], ans[50005];
vector<pair<int, int>> v[50005];
queue<pair<int, int>> que;
bool is[50005];

int main()
{
    in >> n >> m;
    for(int i=1; i<=m; i++) {
        int x, y, c;
        in >> x >> y >> c;
        v[x].pb({y, c});
    }

    for(int i=2; i<=n; i++)
        ans[i] = inf;

    que.push({1, 0});
    is[1] = 1;
    while(!que.empty()) {
        int nod = que.front().first, cost = que.front().second;
        que.pop();

        is[nod] = 0;

        for(int i=0; i<v[nod].size(); i++) {
            int nxt = v[nod][i].first;
            int nxtcost = cost + v[nod][i].second;
            if(is[nxt])
                continue;

            if(nxtcost < ans[nxt]) {
                fr[nxt]++;
                if(fr[nxt] == n) {
                    out << "Ciclu negativ!";
                    return 0;
                }

                que.push({nxt, nxtcost});
                ans[nxt] = nxtcost;
                is[nxt] = 1;
            }
        }
    }

    for(int i=2; i<=n; i++)
        out << ans[i] << ' ';
    return 0;
}