Cod sursa(job #2505636)

Utilizator tziplea_stefanTiplea Stefan tziplea_stefan Data 7 decembrie 2019 09:58:55
Problema Statistici de ordine Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.76 kb
#include <fstream>
#include <cstdlib>

using namespace std;

ifstream fin("sdo.in");
ofstream fout("sdo.out");

const int VAL=3000005;

int N, K, i, j;
int v[VAL];

int Partition(int be, int en)
{
    int pivot=be+(rand()%(en-be+1));
    int i=be, P=v[pivot];
    swap(v[pivot], v[en]);
    for (int j=be; j<=en; j++)
    {
        if (v[j]<=P)
        {
            swap(v[i], v[j]);
            i++;
        }
    }
    return i-1;
}

void Order(int be, int en)
{
    int pos=Partition(be, en);
    if (K==pos)
        return;
    if (K<pos)
        Order(be, pos-1);
    else
        Order(pos+1, en);
}

int main()
{
    fin >> N >> K;
    for (i=1; i<=N; i++)
        fin >> v[i];
    Order(1, N);
    fout << v[K] << '\n';
    fin.close();
    fout.close();
    return 0;
}