LeetCode(88) Merge Sorted Array

题目如下:

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.

分析如下:

题目要求不自己另外申请额外的空间的情况下直接把数组B归并放入数组A。如果从左到右依次遍历，这个没法实现这个要求。所以考虑从右到左遍历。

我的代码:

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

2014-10-09 update 依然是从右向左进行merge 。可以对比这道题目 merge two sorted list

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