Cod sursa(job #2853765)

Utilizator taiwolfgodBogdan Tailup taiwolfgod Data 20 februarie 2022 16:44:59
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.59 kb
#include <fstream>
#include <vector>
#include <queue>
#include <string.h>
#include <iostream>

using namespace std;

#define lim 50010
#define inf 2e9

struct node
{
    int direction;
    int cost;
};

vector<node> G[lim];
///node,cost
priority_queue<pair<int,int>> q;

int N,M;
int rezultat[lim];
bool vizitat[lim];

void dijkstra()
{
    rezultat[1] = false;
    q.push({0, 1});

    while (!q.empty())
    {
        /// use node as currentNode, direction being x not y in this case
        pair<int,int> top = q.top();
        q.pop();
        if(!vizitat[top.second])
        {
            vizitat[top.second] = true;

            for(auto nod : G[top.second])
            {
                if(rezultat[nod.direction] > rezultat[top.second] + nod.cost )
                {
                    rezultat[nod.direction] = rezultat[top.second] + nod.cost;
                    q.push(make_pair(-rezultat[nod.direction],nod.direction));

                }
            }
        }

    }
}

int main() {

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

    int source, destination, cost;
    fin>>N>>M;

    for (int i = 1; i <= M; i++) {
        fin>>source>>destination>>cost;
        G[source].push_back({destination, cost});
    }

    for (int i = 1; i <= N; i++)
        rezultat[i] = inf;

    dijkstra();

    for(int i = 2 ; i <= N ; i++)
    {

        if(rezultat[i] == inf)
            fout<<0<<' ';
        else
            fout<<rezultat[i]<<' ';

    }


    fin.close();
    fout.close();
    return 0;
}