Leetcode Array101 Squares of a Sorted Array by Go

Constraints:
1 <= nums.length <= 104
-104 <= nums[i] <= 104
nums is sorted in non-decreasing order.

My code

func sortedSquares(nums []int) []int {
	for i := range nums {
		nums[i] = square(nums[i])
	}
	nums = bubble(nums)
	return nums
}

func square(n int) int {
	n = n * n
	return n
}

func bubble(nums []int) []int {
	for x := range nums {
		for y := 0; y < len(nums)-x; y++ {
			if y+1 > len(nums)-1 {
				break
			}
			if nums[y] > nums[y+1] {
				buf := nums[y+1]
				nums[y+1] = nums[y]
				nums[y] = buf
			}
		}
	}
	return nums
}

• go.dev/play/p/xhKIDRLSZNg

1) First I made abs function because I thought negative numbers must be positive.
2) So after abs function implemented, I implemented bubble sorting function.
3) After checking sorted number, I implemented square function.
4) So I realized, abs function was not needed.
5) I deleted abs and put only square and bubble function.

Sample 16 ms submission

func sortedSquares(nums []int) []int {
    l := 0
    p := len(nums) - 1
    r := p
    nns := make([]int, p + 1)
    
    for l <= r {
        lv := nums[l] * nums[l]
        rv := nums[r] * nums[r]
        
        if lv > rv {
            nns[p] = lv
            p = p - 1
            l = l + 1
        } else {
            nns[p] = rv
            p = p - 1
            r = r - 1
        }
    }
    
    return nns
}

• I don't know what sort It is.
• But looks clean.
• Checking which number between left end and right end is bigger and put to new slice from End of the slice.

15/02

• I got answer from slack of Nomader code.
• That is a two pointer algorithm
• hongjuzzang.github.io/cs/two_pointers/

sample 6600 KB submission

func sortedSquares(nums []int) []int {
    n:= len(nums)
    result:= make([]int, 0, n)
    for _, v:= range nums{
        result = append(result, v*v)
    }

    for i:=0; i<n-1; i++{
        for j:=0; j<n-i-1; j++{
            if result[j]> result[j+1]{
                result[j], result[j+1]= result[j+1], result[j]
            }
        }
    }
    return result
}

• First Time, When I saw this code, I was confused. because This code looked weird.
• This code also didn't change original arrays.
• After copying them to VSC, I recognized These will copy each other without buffer.
• Bubble sort was used.