AcWing 786. 第k个数
原题链接
简单
作者:
Lumos_18
,
2024-03-04 23:57:53
,
所有人可见
,
阅读 19
第K个数-JAVA
//用BufferRead要写
//import java.io.BufferedReader;
//import java.io.IOException;
//import java.io.InputStreamReader;
import java.util.*;
public class Main {
private static void quick_sort(int[] q, int l, int r) {
if (l >= r)
return;
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 t = q[i];
q[i] = q[j];
q[j] = t;
}
}
quick_sort(q, l, j);
quick_sort(q, j + 1, r);
}
public static void main(String[] args){
Scanner scanner = new Scanner(System.in);
int n = scanner.nextInt();
int k = scanner.nextInt();
int[] q = new int[n];
for (int i = 0; i < n; i++) {
q[i] = scanner.nextInt();
}
quick_sort(q, 0, n - 1);
System.out.print(q[k-1]); //数组用0开始,第k个数在数组中是k-1
}
}