Cod sursa(job #1228218)

Utilizator MarronMarron Marron Data 13 septembrie 2014 10:25:19
Problema Algoritmul lui Dijkstra Scor 0
Compilator cpp Status done
Runda Arhiva educationala Marime 1.31 kb
#include <iostream>
#include <fstream>
#include <algorithm>
#include <vector>
#include <queue>
#include <cstring>
#include <bitset>
using namespace std;

typedef vector< pair<int, int> >::iterator iter;

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

#define MAXN 50005
#define inf 0x3f3f3f3f

int n, m;
vector< pair<int, int> > G[MAXN];
priority_queue< pair<int, int> > pq;
int dist[MAXN];
bitset<MAXN> viz;

int main()
{
    memset(dist, 0x3f, sizeof(dist));

    f >> n >> m;
    for (int i = 1, x, y, c; i <= m; i++) {
        f >> x >> y >> c;
        G[x].push_back(make_pair(y, c));
    }


    dist[1] = 0;
    pq.push(make_pair(0, 1));
    while (!pq.empty()) {
        int nd = pq.top().second;
        pq.pop();

        if (viz[nd] == true) {
            continue;
        }
        viz[nd] = true;

        for (iter it = G[nd].begin(); it != G[nd].end(); it++) {
            if (dist[nd] + it->second < dist[it->first]) {
                dist[it->first] = dist[nd] + it->second;
                pq.push(make_pair(-dist[it->first], it->first));
            }
        }
    }

    for (int i = 2; i <= n; i++) {
        if (dist[i] == inf) {
            cout << 0 << ' ';
        } else {
            cout << dist[i] << ' ';
        }
    }

    return 0;
}