Cod sursa(job #1889426)

Utilizator Burbon13Burbon13 Burbon13 Data 22 februarie 2017 18:37:08
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.31 kb
#include <cstdio>
#include <vector>
#include <queue>

using namespace std;

const int nmx = 50002;
const int inf = 0x3f3f3f3f;

int n,m,dist[nmx];
vector <pair<int,int> > g[nmx];
priority_queue <pair<int,int> > q;

void citire()
{
    scanf("%d %d", &n, &m);
    for(int i = 1; i <= m; ++i)
    {
        int nod1,nod2,cost;
        scanf("%d %d %d", &nod1, &nod2, &cost);
        g[nod1].push_back(make_pair(nod2,cost));
    }
}

void setare_dist()
{
    for(int i = 1; i <= n; ++i)
        dist[i] = inf;
}

void dijkstra()
{
    dist[1] = 0;
    q.push(make_pair(0,1));

    while(not q.empty())
    {
        int nod = q.top().second;
        int dst = -q.top().first;
        q.pop();

        if(dst > dist[nod])
            continue;

        dist[nod] = dst;

        for(vector<pair<int,int> >::iterator it = g[nod].begin(); it != g[nod].end(); ++it)
            if(dist[it->first] > dist[nod] + it->second)
                q.push(make_pair(-(dist[nod] + it->second),it->first));
    }
}

void afish()
{
    for(int i = 2; i <= n; ++i)
        printf("%d ", dist[i] == inf ? 0 : dist[i]);
}

int main()
{
    freopen("dijkstra.in", "r", stdin);
    freopen("dijkstra.out", "w", stdout);
    citire();
    setare_dist();
    dijkstra();
    afish();
    return 0;
}