Cod sursa(job #2572951)

Utilizator BogdanRazvanBogdan Razvan BogdanRazvan Data 5 martie 2020 15:05:41
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.13 kb
#include <bits/stdc++.h>

using namespace std;

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

void usain_bolt()
{
    ios::sync_with_stdio(false);
    fin.tie(0);
}

const int N = 5e4 + 5;

vector < pair < int, int > > a[N];
multiset < pair < int, int > > s;

int d[N];
bool f[N];

void dijkstra(int n)
{
    for(int i = 1; i <= n; ++i) d[i] = 2e9;
    d[1] = 0;
    s.insert({d[1], 1});
    while(!s.empty()) {
        auto x = s.begin();
        s.erase(s.begin());
        int v = x -> second;
        for(auto it : a[v]) {
            int to = it.first;
            int len = it.second;
            if(d[to] > d[v] + len) {
                s.erase({d[to], to});
                d[to] = d[v] + len;
                s.insert({d[to], to});
            }
        }
    }
    for(int i = 2; i <= n; ++i) {
        fout << ((d[i] != 2e9) ? d[i] : 0) << " ";
    }
}
int main()
{
    usain_bolt();

    int n, m;

    fin >> n >> m;
    for(int i = 1; i <= m; ++i) {
        int x, y, w;

        fin >> x >> y >> w;
        a[x].push_back({y, w});
    }
    dijkstra(n);
    return 0;
}