Find the Squares of a Sorted Array in Java


The challenge

Given an array of integers A sorted in non-decreasing order, return an array of the squares of each number, also in sorted non-decreasing order.

Example 1:

Input: [-4,-1,0,3,10]
Output: [0,1,9,16,100]

Example 2:

Input: [-7,-3,2,3,11]
Output: [4,9,9,49,121]

Note:

  1. 1 <= A.length <= 10000
  2. -10000 <= A[i] <= 10000
  3. A is sorted in non-decreasing order.

The solution

class Solution {
    // return the sorted array squared
    public int[] sortedSquares(int[] A) {
        // create a new primitive int array
        int[] res = new int[A.length];
        // loop through the input array
        for (int i=0; i<A.length; i++) {
            // square each value
            res[i] = A[i] * A[i];
        }
        
        // finally sort the array
        Arrays.sort(res);
        
        // return the array
        return res;
    }
}