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]
难度：easy
题目：给定两个有序整数数组 nums1 和 nums2, 合并两数组。注意：nums1 和 nums2 是单独实例化的两个数组长度为 m 和 n。假定 nums1 拥有足够的空间（大于 m +n) 来存放 nums2 中的所有元素。
思路：从后向前处理
Runtime: 2 ms, faster than 100.00% of Java online submissions for Merge Sorted Array.Memory Usage: 26.4 MB, less than 93.33% of Java online submissions for Merge Sorted Array.
class Solution {
public void merge(int[] nums1, int m, int[] nums2, int n) {
int end = m + n – 1;
int ml = m – 1, nl = n – 1;
while (ml >= 0 && nl >= 0) {
nums1[end–] = nums1[ml] > nums2[nl] ? nums1[ml–] : nums2[nl–];
}
while (nl >= 0) {
nums1[end–] = nums2[nl–];
}
}
}