Cod sursa(job #2739497)

Utilizator MateiAruxandeiMateiStefan MateiAruxandei Data 8 aprilie 2021 14:01:25
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.53 kb
#include <bits/stdc++.h>

using namespace std;

const int INF(1 << 30), NMAX(50005);
using VI  = vector<int>;
using VVI = vector<VI>;
using VB  = vector<bool>;
void BUNA(const string& task = "")
{
    if (!task.empty())
        freopen((task + ".in").c_str(), "r", stdin),
                freopen((task + ".out").c_str(), "w", stdout);
    ios::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
}
void PA()
{
    exit(0);
}

VI viz(NMAX, 0), cost(NMAX, INF);
vector<pair<int, int> > G[NMAX];

void Dijkstra()
{
    set<pair<int, int > > s;
    s.insert({0, 1});
    cost[1] = 0;
    while(!s.empty())
    {
        int nod = s.begin()->second;
        s.erase(s.begin());
        viz[nod] = 1;
        for(auto it: G[nod])
            if(viz[it.first] == 0)
            {
                int newC = cost[nod] + it.second;
                if(newC < cost[it.first])
                {
                    if(cost[it.first] != INF)
                        s.erase(s.find({cost[it.first], it.first}));
                    cost[it.first] = newC;
                    s.insert({cost[it.first], it.first});
                }
            }

    }
}

int main()
{
    BUNA("dijkstra");
    int n, m;
    cin >> n >> m;

    for(int i = 1; i <= m; ++i)
    {
        int x, y, c;
        cin >> x >> y >> c;

        G[x].push_back({y, c});
    }

    Dijkstra();
    for(int i = 2; i <= n; ++i)
        if(cost[i] == INF)
            cout << 0 << ' ';
        else cout << cost[i] << ' ';
    PA();
}