Cod sursa(job #2391848)

Utilizator BlaugranasEnal Gemaledin Blaugranas Data 29 martie 2019 12:13:55
Problema Statistici de ordine Scor 0
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.89 kb
#include<cstdio>
#include<cstdlib>
#include<algorithm>
#include<ctime>
using namespace std;
const int M=3000001,R=30000000;
int a[M],n,k,i,o;
char r[N];
inline char N()
{
    if(o==R)
        fread(r,1,R,stdin),o=0;
    return r[o++];
}
inline int A()
{
    int x=0;
    char c=N();
    while(!(c>='0'&&c<='9'))
        c=N();
    while(c>='0'&&c<='9')
        x=x*10+c-'0',c=N();
    return x;
}
inline int P(int a[],int b,int c)
{
	int i=b-1,j=c+1,p=a[b+(rand()%(c-b+1))];
	while(1)
	{
		for(i++;a[i]<p;i++);
		for(j--;a[j]>p;j--);
		if(i<j)
			swap(a[i],a[j]);
		else
			return j;
	}
	return 0;
}
inline void S(int a[],int i,int j,int k)
{
	if(i==j)
		return;
	int q=P(a,i,j),t=q-i+1;
	t>=k?S(a,i,q,k):S(a,q+1,j,k-t);
}
int main()
{
    freopen("sdo.in","r",stdin),freopen("sdo.out","w",stdout);
	for(srand(time(NULL)),n=A(),k=A(),i=1;i<=n;i++)
		a[i]=A();
	S(a,1,n,k),printf("%d",a[k]);
}