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

m and n respectively.

解题思路:

由于题目已经说明A中已有足够的空间容纳B中的元素，所以从A的尾端开始放置元素即可.

解题代码:

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