Cod sursa(job #2423862)

Utilizator mariusilieMarius Ilie mariusilie Data 22 mai 2019 00:43:51
Problema Algoritmul lui Dijkstra Scor 40
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.39 kb
#include <iostream>
#include <fstream>
#include <vector>
#include <queue>
#define NLIM 50001
#define INT_MAX (1<<31)-1

using namespace std;
ifstream f("dijkstra.in");
ofstream g("dijkstra.out");

vector< pair<int, int> > Muchii[NLIM];
bool mark[NLIM];
int dis[NLIM];
struct cmpDis {
    bool operator()(int a, int b) {
        return dis[a] > dis[b];
    }
};

priority_queue<int, vector<int>, cmpDis> Coada;

void citire(int &n, int &m) {
    f >> n >> m;
    for(int i=1; i<=n; i++) dis[i] = INT_MAX;
    for(int i=1; i<=m; i++) {
        int s, d, c;
        f >> s >> d >> c;
        Muchii[s].push_back(make_pair(d, c));
    }
}

void Dijkstra(int start) {
    dis[start] = 0;

    Coada.push(start);
    mark[start] = 1;

    while(!Coada.empty()) {
        int nod = Coada.top();
        Coada.pop();
        mark[start] = 0;

        for(int i=0; i<Muchii[nod].size(); i++) {
            int vecin = Muchii[nod][i].first;
            int cost = Muchii[nod][i].second;

            if(dis[nod]+cost< dis[vecin]) {
                dis[vecin] = dis[nod]+cost;
                if(!mark[vecin]) {
                    Coada.push(vecin);
                    mark[vecin] = 1;
                }
            }
        }
    }
}

int main() {
    int n, m;

    citire(n, m);
    Dijkstra(1);

    for(int i=2; i<=n; i++)
        if(dis[i] != INT_MAX)
            g << dis[i] << ' ';
        else g << "0 ";

    return 0;
}