leetcode链接：
https://leetcode.cn/problems/squares-of-a-sorted-array/description/

方案一

暴力求解：先平方，在排序。

for (int i = 0; i < nums.length; i++)
	nums[i] = nums[i] * nums[i];

Arrays.sort(nums);
return nums;

结果

137/137 cases passed (5 ms)
Your runtime beats 27.58 % of java submissions
Your memory usage beats 38.1 % of java submissions (43.3 MB)

方案二

双指针

int left = 0, 
	right = nums.length -1,
	length = nums.length - 1;

int[] result = new int[nums.length];

while (left <= right) {
	if (nums[left] * nums[left] > nums[right] * nums[right]) {
		result[length--] = nums[left] * nums[left];
		left++;
	} else {
		result[length--] = nums[right] * nums[right];
		right--;
	}
}

return result;