Cod sursa(job #1799575)

Utilizator DawlauAndrei Blahovici Dawlau Data 6 noiembrie 2016 14:58:43
Problema Statistici de ordine Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.82 kb
#include<fstream>
#include<cstdlib>
using namespace std;
ifstream fin("sdo.in");
ofstream fout("sdo.out");
unsigned int v[3000001];
void citire(unsigned int &n,unsigned int &k)
{
    fin>>n>>k;
    for(int i=1;i<=n;++i)
        fin>>v[i];
}
unsigned int quick_select(unsigned int st,unsigned int dr,unsigned int k)
{
    if(st==dr)
        return v[st];
    unsigned int pivot=v[rand()%(dr-st+1)+st],i=st,j=dr;
    while(i<=j)
    {
        while(v[i]<pivot) ++i;
        while(v[j]>pivot) --j;
        if(i<=j)
        {
            swap(v[i],v[j]);
            ++i;
            --j;
        }
    }
    if(k<=j-st+1)
        return quick_select(st,j,k);
    else
        return quick_select(j+1,dr,k-(j-st+1));
}
int main()
{
    unsigned int n,k;
    citire(n,k);
    fout<<quick_select(1,n,k);
}