977. Squares of a Sorted Array
Given an integer array nums sorted in non-decreasing order, return an array of the squares of each number sorted in non-decreasing order.
Example 1:
Input: nums = [-4,-1,0,3,10]
Output: [0,1,9,16,100]
Explanation: After squaring, the array becomes [16,1,0,9,100].
After sorting, it becomes [0,1,9,16,100].
Example 2:
Input: nums = [-7,-3,2,3,11]
Output: [4,9,9,49,121]
Constraints:
- 1 <= nums.length <= 104
- -104 <= nums[i] <= 104
- nums is sorted in non-decreasing order.
Follow up: Squaring each element and sorting the new array is very trivial, could you find an O(n) solution using a different approach?
class Solution {
public int[] sortedSquares(int[] A) {
int n = A.length;
int[] result = new int[n];
int i = 0, j = n - 1;
for (int p = n - 1; p >= 0; p--) {
if (Math.abs(A[i]) > Math.abs(A[j])) {
result[p] = A[i] * A[i];
i++;
} else {
result[p] = A[j] * A[j];
j--;
}
}
return result;
}
}