## DEV Community

Abhishek Chaudhary

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# 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?SOLUTION:

``````class Solution:
def sortedSquares(self, nums: List[int]) -> List[int]:
n = len(nums)
beg = 0
end = n - 1
while beg <= end:
mid = (beg + end) // 2
if nums[mid] > 0 and nums[mid - 1] < 0:
beg = mid
break
elif beg == end:
break
elif nums[mid] < 0:
beg = mid + 1
else:
end = mid
op = []
i = beg - 1
j = beg
while i >= 0 and j <= n - 1:
if nums[i] * nums[i] < nums[j] * nums[j]:
op.append(nums[i] * nums[i])
i -= 1
else:
op.append(nums[j] * nums[j])
j += 1
while i >= 0:
op.append(nums[i] * nums[i])
i -= 1
while j <= n - 1:
op.append(nums[j] * nums[j])
j += 1
return op
``````