text: //
  // Created by hasee on 2020/6/4.
  //
  
  void merge(int *A, int ASize, int m, int *B, int BSize, int n) {
      int cur = m + n - 1;
      int ida = m - 1;
      int idb = n - 1;
      while (ida >= 0 && idb >= 0) {
          A[cur--] = A[ida] >= B[idb] ? A[ida--] : B[idb--];
      }
      while (idb >= 0) {
          A[cur--] = B[idb--];
      }
  }