Merge Sorted Array (Leetcode 88)

Problem Link: https://leetcode.com/problems/merge-sorted-array/

class Solution:
    def merge(self, nums1: List[int], m: int, nums2: List[int], n: int) -> None:
        """
        Do not return anything, modify nums1 in-place instead.
        """
        ptr3=m+n-1
        ptr1=m-1
        ptr2=n-1
        # Start traversing from back
        while(ptr1>=0 and ptr2>=0):
            if(nums1[ptr1]>nums2[ptr2]):
                nums1[ptr3]=nums1[ptr1]
                ptr1=ptr1-1
                ptr3=ptr3-1
            else:
                nums1[ptr3]=nums2[ptr2]
                ptr2=ptr2-1
                ptr3=ptr3-1
            
        # Fill nums1 with left over element of nums2
        while(ptr2>=0):
            nums1[ptr3]=nums2[ptr2]
            ptr2=ptr2-1
            ptr3=ptr3-1