Cod sursa(job #1376454)

Utilizator diana97Diana Ghinea diana97 Data 5 martie 2015 17:27:40
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.19 kb
#include <iostream>
#include <fstream>
#include <set>
#include <vector>

using namespace std;

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

const int INF = (1 << 30);
const int NMAX = 50000 + 1;

int n, m;
int sol[NMAX];
vector <int> graf[NMAX], cost[NMAX];
set < pair <int, int> > s;

void citeste() {
    int a, b, c;
    f >> n >> m;
    for (int i = 1; i <= m; i++) {
        f >> a >> b >> c;
        graf[a].push_back(b);
        cost[a].push_back(c);
    }
}

void dijkstra(int src, int d[]) {
    int l, fiu, nod, c;

    for (int i = 2; i <= n; i++) d[i] = INF;
    s.insert(make_pair(0, src));

    while(!s.empty()) {
        nod = (*s.begin()).second;
        c = (*s.begin()).first;
        s.erase(s.begin());

        l = graf[nod].size();
        for (int i = 0; i < l; i++) {
            fiu = graf[nod][i];
            if (d[fiu] > c + cost[nod][i]) {
                d[fiu] = c + cost[nod][i];
                s.insert(make_pair(d[fiu], fiu));
            }
        }
    }
}

void scrie() {
    for (int i = 2; i <= n; i++) {
        if (sol[i] == INF) sol[i] = 0;
        g << sol[i] << ' ';
    }
}

int main() {
    citeste();
    dijkstra(1, sol);
    scrie();
    return 0;
}