LeetCode-Merge Sorted Array

class Solution {public:    void merge(int A[], int m, int B[], int n) {        // Start typing your C/C++ solution below        // DO NOT write int main() function        int i;        int j;        int last = m + n;        for (i = m - 1, j = n - 1; i >= 0 && j >= 0;)        {            if (A[i] > B[j])            {                A[--last] = A[i--];            }            else            {                A[--last] = B[j--];            }        }        while (j >= 0)        {            A[--last] = B[j--];        }    }};