Cod sursa(job #2528998)

Utilizator flee123Flee Bringa flee123 Data 22 ianuarie 2020 20:31:42
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.56 kb
#include <bits/stdc++.h>
#define nmax 50005
#define infinity 2000000000
using namespace std;
ifstream fin("dijkstra.in");
ofstream fout("dijkstra.out");

struct graf{
    int dest, price;
}var;

vector <graf> graphs[nmax];

int n, m;
bool viz[nmax];
int dist[nmax];

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

};
priority_queue<int, vector <int>, compara> prq;

void citire()
{
    int i, x;
    for(i = 0; i < m; i++)
        fin >> x >> var.dest >> var.price, graphs[x].push_back(var);
    for(i = 1; i <= n; i++)
        dist[i] = infinity;
    dist[1] = 0;
}

void dijkstra(int nod_start)
{
    int node;
    unsigned len, i;
    graf x;
    prq.push(1);
    viz[1] = 1;
    while(!prq.empty())
    {
        node = prq.top();
        prq.pop();
        viz[node] = 0;
        len = graphs[node].size();
        for(i = 0; i < len; i++)
        {
            x = graphs[node][i];
            if(dist[node] + x.price < dist[x.dest])
            {
                dist[x.dest] = dist[node] + x.price;
                if(!viz[x.dest])
                {
                    viz[x.dest] = true;
                    prq.push(x.dest);
                }
            }
        }
    }
}

void afisare()
{
    int i;
    for(i = 2; i <= n; i++)
    {
        if(dist[i] == infinity)
            fout << "0 ";
        else
            fout << dist[i] << ' ';
    }
}

int main()
{
    fin >> n >> m;
    citire();
    dijkstra(1);
    afisare();
    return 0;
}