Cod sursa(job #2012544)

Utilizator workwork work work Data 18 august 2017 23:38:53
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1 kb
#include <bits/stdc++.h>

#define f first
#define s second

using namespace std;

FILE *F=fopen("dijkstra.in", "r"), *G=fopen("dijkstra.out", "w");

int n, m, d[50005], x, y, c;
bitset<50005> w;
vector<pair<int, int> > a[50005];
priority_queue<pair<int, int> > pq;
const int inf = 1 << 30;

int main()
{
    vector<pair<int, int> > :: iterator it;
    fscanf(F, "%d %d ", &n, &m);
    for(int i = 1; i <= m; ++ i)
    {
        fscanf(F, "%d %d %d ", &x, &y, &c);
        a[x].push_back({y, c});
    }
    for(int i = 2; i <= n; ++ i) d[i] = inf;
    pq.push({0, 1});
    while(!pq.empty())
    {
        x = pq.top().s;
        pq.pop();
        if(w[x]) continue;
        w[x] = 1;
        for(it = a[x].begin(); it != a[x].end(); ++ it)
            if(d[(*it).f] > d[x] + (*it).s)
                d[(*it).f] = d[x] + (*it).s, pq.push({-d[(*it).f], (*it).f});
    }
    for(int i = 2;i <= n; ++ i)
        d[i] == inf ? fprintf(G, "%d ", 0) : fprintf(G, "%d ", d[i]);
    return 0;
}