Function to Find the K-th Number

Time limit0.2sMemory limit512 MB

Summary

Given an array of up to 5,000,000 integers and 1-based K, return the element at position K after sorting the array ascending.

Level: Medium4 of 10
Topics: Sorting, Brute force
Solved: No attempts yet

Problem

You are given a sequence $A_1, A_2, \dots, A_N$ of size $N$ . Write a function that returns the $K$ -th number from the front when $A$ is sorted in ascending order.

The function you must write is as follows. $N$ is given as n, $A$ as a, and $K$ as k.

C, C11, C (Clang), C11 (Clang): int kth(int *a, int n, int k);
C++, C++11, C++14, C++17, C++ (Clang), C++11 (Clang), C++14 (Clang), C++17 (Clang): int kth(std::vector<int> &a, int k);
Java, Java (OpenJDK): int kth(int[] a, int k); (class name: Test)
PyPy2, PyPy3: def kth(a: list, k : int) -> int
Go: kth(a []int, k int) int

Constraints

$1 \le N \le 5\,000\,000$
$1 \le K \le N$
$-10^9 \le A_i \le 10^9$

Examples1

Example 1
Input
```
1
0
1
```
Expected output
```
0
```