Pagini recente » Cod sursa (job #195712) | Statistici Vlad Dumitru (Vlad_Dumitru) | Cod sursa (job #1255138) | Cod sursa (job #1091773) | Cod sursa (job #3337543)
#include <fstream>
#include <cstdlib>
using namespace std;
const int N = 3e6;
int v[N], aux[N];
void part3(int v[], int st, int dr, int &p1, int &p2)
{
int poz = rand() % (dr - st + 1) + st;
swap(v[dr], v[poz]);
p1 = st, p2 = dr - 1;
int i = st;
while (i <= p2)
{
if (v[i] == v[dr])
{
i++;
}
else if (v[i] < v[dr])
{
swap(v[i++], v[p1++]);
}
else /// v[i] < v[dr]
{
swap(v[i], v[p2--]);
}
}
swap(v[++p2], v[dr]);
}
void quick_sort(int v[], int st, int dr, int k)
{
if (st >= dr)
{
return;
}
int p1, p2;
part3(v, st, dr, p1, p2);
if (k < p1)
{
quick_sort(v, st, p1 - 1, k);
}
if (k > p2)
{
quick_sort(v, p2 + 1, dr, k);
}
}
int main()
{
ifstream in("sdo.in");
int n, k;
in >> n >> k;
for (int i = 0; i < n; i++)
{
in >> v[i];
}
in.close();
k--;
quick_sort(v, 0, n - 1, k);
ofstream out("sdo.out");
out << v[k] << "\n";
out.close();
return 0;
}