【100题纪念】【有趣的算法】【leetcode题解】【E】【84】Merge Sorted Array

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

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

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主要是利用，数组1比较大的优势，可以从后往前比较，直接从nums1[m+n-1]开始填数

题目的输入也比较败家，nums1的输入，必须保证初始数组的长度就大于m+n才行。

class Solution(object):
    def merge(self, nums1, m, nums2, n):

        pm = m - 1
        pn = n - 1

        pos = m+n-1

        while pos >= 0 and pm >= 0 and pn >= 0:
            #print pos,pm,pn
            if nums1[pm] > nums2[pn]:
                nums1[pos] = nums1[pm]
                pos -= 1
                pm -= 1
            else:
                nums1[pos] = nums2[pn]
                pos -= 1
                pn -= 1
        while pm >= 0:
            nums1[pos] = nums1[pm]
            pos -= 1
            pm -= 1
        while pn >= 0:
            nums1[pos] = nums2[pn]
            pos -= 1
            pn -= 1