[LintCode笔记了解一下]64.合并排序数组

Given two sorted integer arrays A and B, merge B into A as one sorted array.

思路:

因为A的后面的部分都是空的留出来给我们放元素,所以最好是从后往前塞元素进去

    void mergeSortedArray(int A[], int m, int B[], int n) {
        // write your code here
        int i = m-1;
        int j = n-1;
        int index = m+n-1;
        while(i>=0&&j>=0){
            if(A[i]>=B[j]){
                A[index]=A[i];
                index--;
                i--;
            }else{
                A[index]=B[j];
                index--;
                j--;
            }
        }
        while(i>=0){
            A[index--]=A[i--];
        }
        while(j>=0){
            A[index--]=B[j--];
        }
    }