Cod sursa(job #2905810)

Utilizator lifusorin.13Lifu Sorin lifusorin.13 Data 23 mai 2022 19:37:52
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.32 kb
#include <bits/stdc++.h>

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

vector < pair <int, int> > v[50001];
int n, m, a, b, c, dist[50001];

struct cmp
{
    bool operator()(pair<int, int> a, pair<int, int> b)
    {
        return a.first > b.first;
    }
};

priority_queue<pair<int, int>, vector<pair<int, int> >, cmp>q;
bool was[50001];


void djk(int st)
{
    for (int i = 1; i <= n; i++)
        dist[i] = (1 << 30);
    dist[st] = 0;
    q.push({0, st});
    while(!q.empty()){
        pair <int, int> nod = q.top();
        q.pop();
        if (was[nod.second])
            continue;
        was[nod.second] = 1;
        for (int i = 0; i < v[nod.second].size(); i++) {
            pair<int, int> vecin = v[nod.second][i];
            if (nod.first + vecin.second < dist[vecin.first]) {
                dist[vecin.first] = nod.first + vecin.second;
                q.push({dist[vecin.first], vecin.first});
            }
        }
    }
}

int main()
{
    fin >> n >> m;
    for (int i = 1; i <= m; i++) {
        fin >> a >> b >> c;
        v[a].push_back({b, c});
    }
    djk(1);
    for (int i = 2; i <= n; i++) {
        if (dist[i] == (1<<30))
            dist[i] = 0;
        fout << dist[i] << " ";
    }
    fout << "\n";
    return 0;
}