mergeInPlace.py

# Merge Sorted Array


# Given two sorted integer arrays nums1 and nums2, merge nums2 into nums1 as one sorted array.

# Note:

# The number of elements initialized in nums1 and nums2 are m and n respectively.
# You may assume that nums1 has enough space (size that is equal to m + n) to hold additional elements from nums2.
# Example:

# Input:
# nums1 = [1,2,3,0,0,0], m = 3
# nums2 = [2,5,6],       n = 3

# Output: [1,2,2,3,5,6]
 

# Constraints:

# -10^9 <= nums1[i], nums2[i] <= 10^9
# nums1.length == m + n
# nums2.length == n
   # Hide Hint #1  
# You can easily solve this problem if you simply think about two elements at a time rather than two arrays. We know that each of the individual arrays is sorted. What we don't know is how they will intertwine. Can we take a local decision and arrive at an optimal solution?
   # Hide Hint #2  
# If you simply consider one element each at a time from the two arrays and make a decision and proceed accordingly, you will arrive at the optimal solution.

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.
        """
        nums1[m:] = nums2
        nums1.sort()