#https://leetcode.com/problems/merge-sorted-array/ class Solution(object): def merge(self, nums1, m, nums2, n): #Compare nums1 and nums2 from backward #Put the larger one to nums1's end #If one of the array is done #The rest is already sorted #Just put them in place i = m+n-1 #cursor on nums1 that we are editting i1 = m-1 #cursor on nums1 i2 = n-1 #cursor on nums2 while i1>=0 and i2>=0: if nums1[i1]>nums2[i2]: nums1[i] = nums1[i1] i1 = i1-1 i = i-1 else: nums1[i] = nums2[i2] i2 = i2-1 i = i-1 #One of the array is done, put the rest in place nums1[:i2+1] = nums2[:i2+1]