Cod sursa(job #3208647)

Utilizator camelia22Dragoiu Camelia camelia22 Data 29 februarie 2024 10:45:56
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.47 kb
#include <iostream>
#include <fstream>
#include <queue>
#include <vector>
#define N 50005
#define maxi 2000000000

using namespace std;

ifstream f("dijkstra.in");
ofstream g("dijkstra.out");

int n, m, dist[N], viz[N];
vector < pair < int, int > > G[N];
struct compara
{
    bool operator() (int x, int y)
    {
        return dist[x] > dist[y];
    }
};
priority_queue < int, vector < int >, compara > coada;

void dijkstra(int nod)
{
    int x, vecin, cost;
    for (int i = 1; i <= n; i++)
        dist[i] = maxi;

    dist[nod] = 0;
    coada.push(nod);
    while (!coada.empty())
    {
        x=coada.top(); viz[x]=0;
        coada.pop();
        for (size_t i=0; i < G[x].size(); i++)
        {
            vecin = G[x][i].first;
            cost = G[x][i].second;
            if (dist[x]+cost < dist[vecin])
            {
                dist[vecin] = dist[x]+cost;
                if (!viz[vecin])
                {
                    coada.push(vecin); viz[vecin] = 1;
                }
            }
        }
    }
}

void citire()
{
    int x, y, c, i;
    for (i = 1; i <= m; i++)
    {
        f >> x >> y >> c;
        G[x].push_back(make_pair(y,c));
    }
}

void afis()
{
    int i;
    for (i = 2; i <= n; i++)
        if (dist[i] != maxi)
            g << dist[i] << " ";
        else
            g << 0 << " ";
}

int main()
{
    f >> n >> m;
    citire();
    dijkstra(1);
    afis();
    return 0;
}