Merge Sorted Array（合并两个有序数组到其中一个数组中）

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 to hold additional elements from B. The number of elements initialized in A and B are m and n respectively.

题意要把两个有序的数组合并到他们中的一个数组中。

唯一的技巧就是从结尾开始归并，不会覆盖元素又能满足题意。

class Solution {  
public:  
    void merge(int A[], int m, int B[], int n) {  
        int i,j,k;  
        for(i=m-1,j=n-1,k=m+n-1;k>=0;--k)  
        {  
            if(i>=0&&(j<0||A[i]>B[j]))  
            {  
                A[k]=A[i--];  
            }  
            else A[k]=B[j--];  
        }  
    }  
};