Cod sursa(job #2350520)

Utilizator fremenFremen fremen Data 21 februarie 2019 15:04:02
Problema Algoritmul Bellman-Ford Scor 50
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.29 kb
#include <fstream>
#include <cstring>
#include <algorithm>
#include <queue>
#include <vector>
#include <climits>
using namespace std;

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

const int MAXN = 50005;
int n, m;
vector<pair<int, int>> v[MAXN];
queue<int> q;
bool inq[MAXN];
int viz[MAXN];
int d[MAXN];


int main() {

    fin >> n >> m;
    for (int i = 1; i <= m; ++i) {
        int a, b, c;
        fin >> a >> b >> c;
        v[a].push_back(make_pair(b, c));
        d[i] = INT_MAX;
    }

    d[1] = 0;
    viz[1] = 1;
    inq[1] = 1;
    q.push(1);
    while(!q.empty()) {
        int node = q.front();
        inq[node] = 0;
        if (viz[node] >= n) {
            fout << "Ciclu negativ!";
            return 0;
        }
        for (int i = 0; i < v[node].size(); ++i) {
            int k = v[node][i].first;
            int c = v[node][i].second;
            if (d[k] > d[node] + c) {
                d[k] = d[node] + c;
                if (inq[k] == 0) {
                    viz[k]++;
                    inq[k] = 1;
                    q.push(k);
                }
            }
        }
        q.pop();
    }

    for (int i = 2; i <= n; ++i) {
        fout << d[i] << ' ';
    }

    fout.close();
    return 0;
}