Cod sursa(job #2476348)

Utilizator avramraresAvram Rares Stefan avramrares Data 18 octombrie 2019 18:07:54
Problema Algoritmul lui Dijkstra Scor 20
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.12 kb
#include <bits/stdc++.h>

using namespace std;
#define inf 0x3f3f3f3f
#define Nmax 50003
ifstream f("dijkstra.in");
ofstream g("dijkstra.out");
int D[Nmax],c,n,m,x,y,k,cost;
bool sel[Nmax];
vector <pair<int,int>> G[Nmax];
priority_queue <pair<int,int>, vector <pair<int,int>>, greater <pair<int,int>>> Q;
void dijkstra()
{
    sel[1]=true;
    for(auto i:G[1])
    {
        Q.push(i);
        D[i.second]=i.first;
    }
    while(!Q.empty())
    {
        while(!Q.empty() && sel[Q.top().second])
            Q.pop();
        if(!Q.empty())
        {
            c=Q.top().first;
            k=Q.top().second;
            sel[k]=true;
            Q.pop();
            for(auto i:G[k])
            {
                if(D[i.second]>D[k]+i.first)
                    D[i.second]=D[k]+i.first, Q.push(i);
            }
        }
    }
}
int main()
{
    f>>n>>m;
    for(int i=1; i<=m; i++)
    {
        f>>x>>y>>cost;
        G[x].push_back({cost,y});
    }
    D[1]=0;
    for(int i=1; i<=n; i++)
        D[i]=inf;
    dijkstra();
    for(int i=2; i<=n; i++)
        g<<D[i]<<" ";
    return 0;
}