Niuke: merging two ordered arrays

The idea of merging here is very simple , Is to compare the size of the elements .

But there are a few details to note , We put it from the back to the front , Because if from now on, if B The elements of are occupying A Front position , that A The element of is thrown away .

secondly , Be aware that when you finally deal with unsorted elements , Only B It needs to be handled before it is finished , because A If you haven't finished , and B It's over ,A In fact, the previous elements can be kept in place .

The code is as follows ：

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--]=A[i--];
            }else{
                A[k--]=B[j--];
            }
        }
        if(i<0){
            while(j>=0){
                A[k--]=B[j--];
            }
        }
    }
};