merge-sorted-array-LeetCode

题目：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.

代码：

      1）版本一：

 1 public void merge1(int A[], int m, int B[], int n) {
 2         int a = m - 1;
 3         int b = n - 1;
 4         int c = m + n -1;
 5         while(a >= 0 && b >= 0){
 6             A[c--] = A[a] > B[b] ? A[a--]:B[b--];
 7         }
 8         while(a >= 0)
 9             A[c--] = A[a--];
10         while(b >= 0)
11             A[c--] = B[b--];
12     }

　　2）版本二：

1 public void merge2(int A[], int m, int B[], int n){
2         for(int i = 0;i < n;i++){
3             A[m+i]=B[i];
4         }
5         Arrays.sort(A);
6     }

重点：二个版本的区别在于一自己写了过程使用从后往前插，避免大量移动元素。二将B拼接到A后，调用库排序。二者都能达到题目要求。