Leetcode:Merge Sorted Array

Given two sorted integer arrays A and B, merge B into A as one sorted array.

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

分析：本题的难点在于是将排序的结果放在数组A中，解决方法是按descending的顺序从后往前遍历A和B。代码如下：

class Solution {
public:
    void merge(int A[], int m, int B[], int n) {
       int lasta = m-1, lastb = n-1, cur = m+n-1;
       while(lasta >= 0 && lastb >= 0){
           A[cur--] = (A[lasta] >= B[lastb])?A[lasta--]:B[lastb--];
       }
       while(lastb >= 0){
           A[cur--] = B[lastb--];
       }
    }
};