Cod sursa(job #2346383)

Utilizator Robys01Robert Sorete Robys01 Data 17 februarie 2019 16:48:56
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.36 kb
#include <iostream>
#include <fstream>
#include <vector>
#include <queue>
#define NMAX 50005
using namespace std;

ifstream fin("dijkstra.in");
ofstream fout("dijkstra.out");

const int inf = (1<<30);

int n, m;
int D[NMAX];
bool InCoada[NMAX];

struct compara{
    bool operator()(int x, int y){
        return D[x] > D[y];
    }

};

vector < pair <int, int> > A[NMAX];
priority_queue < int, vector<int>, compara> Q;


void citire(){
    fin>>n>>m;
    for(; m; m--){
        int i, j, c; fin>>i>>j>>c;
        A[i].push_back(make_pair(j, c));
    }
}

void Dijkstra(int sursa){
    for(int i=1; i<=n; i++)
        D[i] = inf;
    D[sursa] = 0;

    Q.push(sursa);
    InCoada[sursa] = true;
    while(!Q.empty()){
        int Varf = Q.top();
        Q.pop();
        InCoada[Varf] = false;

        for(size_t i = 0; i<A[Varf].size(); i++){
            int Vecin = A[Varf][i].first;
            int Cost = A[Varf][i].second;

            if(D[Vecin] > D[Varf] + Cost){
                D[Vecin] = D[Varf] + Cost;
                if(!InCoada[Vecin]){
                    Q.push(Vecin);
                    InCoada[Vecin] = true;
                }
            }

        }
    }

}


int main(){

    citire();
    Dijkstra(1);

    for(int i=2; i<=n; i++)
        fout<<(D[i]!=inf ? D[i] : 0 )<<' ';

    return 0;
}