```
public class Solution {
public void merge(int[] nums1, int m, int[] nums2, int n) {
int swap_des = m + n - 1;
int p1 = m - 1;
int p2 = n - 1;
while (p1 >= 0 && p2 >= 0)
nums1[swap_des--] = nums1[p1] > nums2[p2]? nums1[p1--]: nums2[p2--];
while (p2 >= 0) nums1[swap_des--] = nums2[p2--];
}
}
```