Cod sursa(job #868320)

Utilizator visanrVisan Radu visanr Data 30 ianuarie 2013 21:52:35
Problema Algoritmul lui Dijkstra Scor 10
Compilator cpp Status done
Runda Arhiva educationala Marime 1.29 kb
#include <cstdio>
#include <cstdlib>
#include <queue>
#include <cstring>
#include <vector>
#include <algorithm>
using namespace std;

#define PI pair<int, int>
#define IT vector<PI> :: iterator
#define pb push_back
#define Inf 0x3f3f3f3f
#define mp make_pair
#define Nmax 50010

int N, M, X, Y, C, Dist[Nmax];
vector<PI> G[Nmax];
priority_queue<PI, vector<PI>, greater<PI> > Q;


void Dijkstra()
{
    memset(Dist, Inf, sizeof(Dist));
    Dist[1] = 0;
    Q.push(mp(0, 1));
    while(!Q.empty())
    {
        int Node = Q.top().second;
        Q.pop();
        bool Stop = true;
        for(IT it = G[Node].begin(); it != G[Node].end(); ++it)
            if(Dist[it -> first] > Dist[Node] + it -> second)
            {
                Stop = false;
                Dist[it -> first] = Dist[Node] + it -> second;
                Q.push(mp(Dist[it -> first], it -> first));
            }
        if(Stop) break;
    }
}

int main()
{
    freopen("dijkstra.in", "r", stdin);
    freopen("dijkstra.out", "w", stdout);
    scanf("%i %i", &N, &M);
    for(int i = 1; i <= M; i++)
    {
        scanf("%i %i %i", &X, &Y, &C);
        G[X].pb(mp(Y, C));
    }
    Dijkstra();
    for(int i = 2; i <= N; i++) printf("%i ", (Dist[i] == Inf ? 0 : Dist[i]));
    return 0;
}