Cod sursa(job #3213293)

Utilizator andreea_chivuAndreea Chivu andreea_chivu Data 12 martie 2024 20:54:42
Problema Algoritmul lui Dijkstra Scor 20
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.14 kb
#include <iostream>
#include <fstream>
#include <vector>
#include <queue>

using namespace std;

const int NMAX = 5e4+1;
const int INF = 5e6+1;

vector <pair<int, int>> s[NMAX];
priority_queue <pair<int, int>, vector<pair<int, int>>, greater<pair<int, int>>> pq;
int d[NMAX];


void dijkstra(int n){
    for(int i = 0; i <= n; i++){
        d[i] = INF;
    }

    int start = 1;

    d[start] = 0;
    pq.push({0, start});

    while(!pq.empty()){
        int x = pq.top().second;
        pq.pop();
        for(auto y: s[x]){
            int nd = y.second;
            int cd = y.first;
            if(d[nd] > d[x] + cd){
                d[nd] = d[x] + cd;
                pq.push({d[nd], nd});
            }
        }
    }
}

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

    int n, m;
    fin >> n >> m;

    for(int i = 0; i < m; i++){
        int a, b, c;
        fin >> a >> b >> c;
        s[a].push_back(make_pair(c, b));
    }

    dijkstra(n);

    for(int i = 2; i <= n; i++)
        fout << d[i] << " ";

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