Merge Sorted Array

Merge Sorted Array

问题：

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 andn respectively.

思路：

　　归并排序的收尾工作 + 正着需要移动 那我们就反着来嘛

我的代码：

public class Solution {
    public void merge(int A[], int m, int B[], int n) {
        if(A == null || B == null || m + n == 0)    return;
        int last = m + n - 1;
        int i = m - 1, j = n - 1;
        while(i >= 0 && j >= 0)
        {
            if(A[i] > B[j])
            {
                A[last--] = A[i--];
            }
            else
            {
                A[last--] = B[j--];
            }
        }
        while(i >= 0)
            A[last--] = A[i--];
        while(j >= 0)
            A[last--] = B[j--];
        return;
    }
}