# [Archived]
# https://leetcode.com/problems/merge-sorted-array/
# 88. Merge Sorted Array

# History:
# Google, Facebook, Netflix
# 1.
# Mar 14, 2020
# 2.
# Apr 22, 2020
# 3.
# Jun 7, 2020

# 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 greater or 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]


class Solution(object):
    def merge(self, nums1, m, nums2, n):
        """
        :type nums1: List[int]
        :type m: int
        :type nums2: List[int]
        :type n: int
        :rtype: None Do not return anything, modify nums1 in-place instead.
        """
        while m + n - 1 >= 0:
            if m - 1 >= 0 and n - 1 >= 0:
                if nums1[m - 1] >= nums2[n - 1]:
                    nums1[m + n - 1] = nums1[m - 1]
                    m -= 1
                else:
                    nums1[m + n - 1] = nums2[n - 1]
                    n -= 1
            elif m - 1 >= 0:
                return
            else:
                nums1[m + n - 1] = nums2[n - 1]
                n -= 1


class Solution2(object):
    def merge(self, nums1, m, nums2, n):
        """
        :type nums1: List[int]
        :type m: int
        :type nums2: List[int]
        :type n: int
        :rtype: None Do not return anything, modify nums1 in-place instead.
        """
        curr = m + n - 1

        n1_p = m - 1
        n2_p = n - 1

        while curr >= 0:
            if n1_p >= 0 and n2_p >= 0:
                if nums1[n1_p] >= nums2[n2_p]:
                    nums1[curr] = nums1[n1_p]
                    n1_p -= 1
                else:
                    nums1[curr] = nums2[n2_p]
                    n2_p -= 1
            elif n1_p >= 0:
                return
            else:
                nums1[curr] = nums2[n2_p]
                n2_p -= 1

            curr -= 1
