Cod sursa(job #2125430)

Utilizator B_RazvanBaboiu Razvan B_Razvan Data 8 februarie 2018 14:39:54
Problema Algoritmul lui Dijkstra Scor 20
Compilator cpp Status done
Runda Arhiva educationala Marime 1.3 kb
#include <iostream>
#include <cstdio>
#include <vector>
#include <queue>
#define NMAX 50005
#define INF 0x3f3f3f

using namespace std;

int N, M, dist[NMAX];
bool viz[NMAX];
vector <pair <int, int> > G[NMAX];
vector <pair <int, int> >::iterator it;
priority_queue <pair <int, int> > Q;

void read()
{
    scanf("%d %d", &N, &M);
    for(int i=1; i<=M; ++i)
    {
        int a, b, c;
        scanf("%d %d %d", &a, &b, &c);
        G[a].push_back(make_pair(b, c));
    }
    for(int i=1; i<=N; ++i)
        dist[i] = INF;
    dist[1] = 0;
}

void dijkstra()
{
    Q.push(make_pair(0, 1));
    while(!Q.empty())
    {
        int nod = Q.top().second;
        int cost = -1 * Q.top().first;
        Q.pop();
        if(dist[nod] != cost)
            continue;
        for(it = G[nod].begin(); it != G[nod].end(); ++it)
            if(dist[it->first] > dist[nod] + it->second)
            {
                dist[it->first] = dist[nod] + it->second;
                Q.push(make_pair(-1*dist[it->first], it->first));
            }
    }
}

void print()
{
    for(int i=2; i<=N; ++i)
        printf("%d ", dist[i]);
}

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