AcWing 786. 第k个数(Java)
原题链接
简单
作者:
火球大的脸盆
,
2022-07-06 18:42:19
,
所有人可见
,
阅读 136
import java.util.Scanner;
public class Main {
public static int quickSort(int q[], int l, int r, int k) {
if (l >= r) return q[l];
int x = q[l + r >> 1], i = l - 1, j = r + 1;
while (i < j) {
do i++; while (q[i] < x);
do j--; while (q[j] > x);
if (i < j) {
int tmp = q[i];
q[i] = q[j];
q[j] = tmp;
}
}
int s = j - l + 1;
if (k <= s) return quickSort(q, l, j, k);
else return quickSort(q, j + 1, r, k - s);
}
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
int n = sc.nextInt(), k = sc.nextInt();
int[] q = new int[100010];
for (int i = 0; i < n; i++) {
q[i] = sc.nextInt();
}
int res = quickSort(q, 0, n - 1, k);
System.out.println(res);
}
}