Cod sursa(job #3042010)

Utilizator RalucaioneteRalucaIonete Ralucaionete Data 3 aprilie 2023 15:24:27
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.35 kb
#include <fstream>
#include<queue>
using namespace std;

ifstream cin("dijkstra.in");
ofstream cout("dijkstra.out");

const int N=5e4, INF=1e9;
int d[N+1], p[N+1], n;
priority_queue<pair<int, int>> q;

struct muchii
{
    int vecin;
    int cost;
};

vector <vector<muchii>> g(N+1);

void afisare()
{
    for(int i=2; i<=n; i++)
    {
        if(d[i]==INF)
            cout << 0 << " ";
        else cout << d[i] << " ";
    }
}


void dijkstra()
{
    while(!q.empty())
    {
        pair <int, int> nod=q.top();
        q.pop();
        int x=nod.second;
        nod.first=-nod.first;
        if(nod.first != d[x])
            continue;
        for(auto y: g[x])
        {
            if(d[x] + y.cost < d[y.vecin])
            {
                d[y.vecin]= d[x] + y.cost;
                p[y.vecin]=x;
                q.push(make_pair(-d[y.vecin], y.vecin));
                // cout << d[y.vecin] << " " << y.vecin << '\n';
            }
        }

    }
    afisare();

}

int main()
{
    int 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});
    }
    d[1]=0;
    for(int i=2; i<=n; i++)
        d[i]=INF;
    for(int i=1; i<=n; i++)
        p[i]=0;
    q.push(make_pair(0,1));
    dijkstra();
    return 0;
}