Cod sursa(job #1979559)

Utilizator nicu_serteSerte Nicu nicu_serte Data 10 mai 2017 20:38:53
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.35 kb
#include <fstream>
#include <vector>
#include <climits>
#include <queue>
using namespace std;
ifstream fin("dijkstra.in");
ofstream fout("dijkstra.out");
#define nmax 50005
#define inf INT_MAX
int n, m, d[nmax], h;
vector<pair<int, int> > g[nmax];
priority_queue<pair<int, int>, vector<pair<int, int> >, greater<pair<int, int> > > pq;
void citire()
{
    int i, x, y, c;
    fin>>n>>m;
    for(i=1; i<=m; i++)
    {
        fin>>x>>y>>c;
        g[x].push_back(make_pair(y, c));
    }
    fin.close();
}
void afisare()
{
    for(int i=2; i<=n; i++)
        if(d[i]==inf)
            fout<<0<<' ';
        else fout<<d[i]<<' ';
    fout<<'\n';
    fout.close();
}
void dijkstra(int p)
{
    vector<pair<int, int> >::iterator it;
    int i;
    bool viz[nmax]={0};
    int k;
    for(i=1; i<=n; i++)
        d[i]=inf;
    d[p]=0;
    pq.push(make_pair(d[p], p));
    while(!pq.empty())
    {
        k=pq.top().second;
        pq.pop();
        if(!viz[k])
        {
            viz[k]=1;
            for(it=g[k].begin(); it!=g[k].end(); it++)
                if(d[it->first]>d[k]+it->second)
                {
                    d[it->first]=d[k]+it->second;
                    if(!viz[it->first])
                        pq.push(make_pair(d[it->first], it->first));
                }
        }
    }
}
int main()
{
    citire();
    dijkstra(1);
    afisare();
    return 0;
}