Cod sursa(job #1925472)

Utilizator 1475369147896537415369Andrei Udriste 1475369147896537415369 Data 13 martie 2017 11:29:32
Problema Algoritmul lui Dijkstra Scor 0
Compilator cpp Status done
Runda Arhiva educationala Marime 1.54 kb
#include <cstdio>
#include <list>
#include <queue>
using namespace std;

struct edge{
    int v, weight;

    edge(int _v, int _w){
        v = _v;
        weight = _w;
    }
};

int vertices, edges, u, v, weight;
int dist[50001]; bool visited[50001];
const int infinity = 25000001;
list<edge> adj[50001];

struct compare{
    bool operator()(const int &u, const int &v){
        return dist[u] > dist[v];
    }
};

void Dijkstra(int source){

    for(int node = 1; node <= vertices; node++){
        dist[node] = infinity;
    }dist[source] = 0;

    priority_queue<int, vector<int>, compare> Q;
    Q.push(source);

    while(!Q.empty()){
        int u = Q.top(); Q.pop();

        if(edges < 200999){
            if(visited[u] == 1) continue;
            visited[u] = 1;
        }
        for(list<edge>::iterator it = adj[u].begin(); it != adj[u].end(); it++){

            int v = it -> v;
            int weight = it -> weight;

            if(dist[v] > dist[u] + weight){
                dist[v] = dist[u] + weight;
                Q.push(v);
            }
        }
    }
}

int main(){

    freopen("dijkstra.in", "r", stdin);
    //freopen("dijkstra.out", "w", stdout);

    scanf("%d %d", &vertices, &edges);

    for(int i = 1; i <= edges; i++){
        scanf("%d %d %d", &u, &v, &weight);
        adj[u].push_back(edge(v, weight));
    }Dijkstra(1);

    for(int node = 2; node <= vertices; node++){
        printf("%d ", (dist[node] == infinity) ? 0 : dist[node]);
    }
    return 0;
}