Cod sursa(job #2175252)

Utilizator PrEaDiVviNAlexandru Hutu PrEaDiVviN Data 16 martie 2018 16:15:57
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.36 kb
#include <bits/stdc++.h>

using namespace std;

ifstream f("dijkstra.in");
ofstream g("dijkstra.out");

const int inf=(1<<30);
#define nmax 50001

int n,m,viz[nmax],d[nmax],tata[nmax];

struct cmp
{
    bool operator()(int x,int y){return d[x]>d[y];}
};

vector < pair <int , int > > lista[nmax];

priority_queue<int , vector <int>, cmp> coada;

void citire()
{
    f>>n>>m;
    for(int i=1;i<=m;i++)
    {
        int x,y,c;
        f>>x>>y>>c;
        lista[x].push_back(make_pair(y,c));
    }
}
void dijkstra(int sursa)
{
    for(int i=1;i<=n;i++)
        d[i]=inf;
    d[sursa]=0;
    viz[sursa]=1;
    tata[sursa]=-1;
    coada.push(sursa);
    while(!coada.empty())
    {
        int nod=coada.top();
        coada.pop();
        viz[nod]=false;
        for(int i=0;i<lista[nod].size();i++)
        {
            int vecin=lista[nod][i].first;
            int cost=lista[nod][i].second;
            if(d[vecin]>d[nod]+cost)
            {
                d[vecin]=d[nod]+cost;
                if(!viz[vecin])
                {
                    viz[vecin]=true;
                    tata[vecin]=nod;
                    coada.push(vecin);
                }
            }
        }
    }
}

int main()
{
    citire();
    dijkstra(1);
    for(int i=2;i<=n;i++)
        if(d[i]==inf)g<<0<<' ';
        else g<<d[i]<<' ';
}