Sort an Array
<p>Given an array of integers <code>nums</code>, sort the array in ascending order and return it.</p>

<p>You must solve the problem <strong>without using any built-in</strong> functions in <code>O(nlog(n))</code> time complexity and with the smallest space complexity possible.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>

<pre>
<strong>Input:</strong> nums = [5,2,3,1]
<strong>Output:</strong> [1,2,3,5]
<strong>Explanation:</strong> After sorting the array, the positions of some numbers are not changed (for example, 2 and 3), while the positions of other numbers are changed (for example, 1 and 5).
</pre>

<p><strong class="example">Example 2:</strong></p>

<pre>
<strong>Input:</strong> nums = [5,1,1,2,0,0]
<strong>Output:</strong> [0,0,1,1,2,5]
<strong>Explanation:</strong> Note that the values of nums are not necessarily unique.
</pre>

<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li><code>1 &lt;= nums.length &lt;= 5 * 10<sup>4</sup></code></li>
	<li><code>-5 * 10<sup>4</sup> &lt;= nums[i] &lt;= 5 * 10<sup>4</sup></code></li>
</ul>
Array; Divide and Conquer; Bucket Sort; Counting Sort; Radix Sort; Sorting; Heap (Priority Queue); Merge Sort
func sortArray(nums []int) []int {
	quickSort(nums, 0, len(nums)-1)
	return nums
}

func quickSort(nums []int, l, r int) {
	if l >= r {
		return
	}
	i, j := l-1, r+1
	x := nums[(l+r)>>1]
	for i < j {
		for {
			i++
			if nums[i] >= x {
				break
			}
		}
		for {
			j--
			if nums[j] <= x {
				break
			}
		}
		if i < j {
			nums[i], nums[j] = nums[j], nums[i]
		}
	}
	quickSort(nums, l, j)
	quickSort(nums, j+1, r)
}