Cod sursa(job #2640968)

Utilizator stefantagaTaga Stefan stefantaga Data 9 august 2020 13:31:29
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.51 kb
#include <bits/stdc++.h>

using namespace std;
ifstream f("dijkstra.in");
ofstream g("dijkstra.out");
int n,m,i,x,y,val,minim[50005],nod,nr,sel[50005],cost;
vector <pair <int,int> > v[50005];
priority_queue <pair <int,int> , vector <pair<int,int> > ,greater <pair <int,int> > > h;
int main()
{
    f>>n>>m;
    for (i=1;i<=m;i++)
    {
        f>>x>>y>>val;
        v[x].push_back({y,val});
    }
    for (i=1;i<=n;i++)
    {
        minim[i]=-1;
    }
    minim[1]=0;
    sel[1]=1;
    for (i=0;i<v[1].size();i++)
    {
        nod=v[1][i].first;
        minim[nod]=v[1][i].second;
        h.push({minim[nod],nod});
    }
    nr=v[1].size();
    while (nr)
    {
        while (!h.empty()&&sel[h.top().second]==1)
        {
            h.pop();
        }
        nod=h.top().second;
        sel[nod]=1;
        cost=h.top().first;
        h.pop();
        nr--;
        for (i=0;i<v[nod].size();i++)
        {
            int nod1=v[nod][i].first;
            if (minim[nod1]==-1)
            {
                minim[nod1]=cost+v[nod][i].second;
                nr++;
                h.push({minim[nod1],nod1});
            }
            else
            if (minim[nod1]>cost+v[nod][i].second)
            {
                minim[nod1]=cost+v[nod][i].second;
                h.push({minim[nod1],nod1});
            }
        }
    }
    for (i=2;i<=n;i++)
    {
        if (minim[i]==-1)
        {
            minim[i]=0;
        }
        g<<minim[i]<<" ";
    }
    return 0;
}