题目描述

blablabla

样例

#include <iostream>

using namespace std;

void qsort(int A[], int begin, int end) {
    if (begin >= end)
        return;
    int x = A[(begin + end) / 2];
    int tmp = 0;
    int left = begin - 1, right = end + 1;
    while (left < right) {
        do left++; while (A[left] < x);
        do right--; while (A[right] > x);
        if (left < right) {
            tmp = A[right];
            A[right] = A[left];
            A[left] = tmp;
        }
    }
    qsort(A, begin, right);
    qsort(A, right + 1, end);
}


int main() {
    int n, k;
    scanf("%d", &n);
    scanf("%d", &k);
    int A[n];
    for (int i = 0; i < n; i++) scanf("%d", &A[i]);
    qsort(A, 0, n - 1);
    printf("%d", A[k - 1]);
}

算法1

(暴力枚举) $O(n^2)$

blablabla

时间复杂度

参考文献

C++ 代码

blablabla

算法2

(暴力枚举) $O(n^2)$

blablabla

时间复杂度

参考文献

C++ 代码

blablabla