注意范围变了,是1-100000了
#include<iostream>
using namespace std;
const int N = 100010;
int n;
int a[N];
int k;
void quick_sort(int st,int ed){
if(st >= ed) return;
int i = st - 1;
int j = ed + 1;
int k = a[(st + ed) / 2];
while(i < j){
do{i++;}while(a[i] < k);
do{j--;}while(a[j] > k);
if(i < j){
int tmp = a[i];
a[i] = a[j];
a[j] = tmp;
}
}
quick_sort(st,j);
quick_sort(j+1,ed);
}
void solve(){
cin >> n;
cin >> k;
for(int i = 1;i <= n;i++) cin >> a[i];
quick_sort(1,n);
cout << a[k];
}
int main(){
solve();
}