Merge Sorted Array

题目
Given two sorted integer arrays nums1 and nums2, merge nums2 into nums1 as one sorted array.

Note:
You may assume that nums1 has enough space (size that is greater or equal to m + n) to hold additional elements from nums2. The number of elements initialized in nums1 and nums2 are m and n respectively.

答案

class Solution {
    public void merge(int[] nums1, int m, int[] nums2, int n) {
        int i = m - 1, j = n - 1, k = m + n - 1;
        while(i >= 0 || j >= 0) {
            if(i >= 0 && j >= 0) {
                if(nums1[i] >= nums2[j])
                    nums1[k--] = nums1[i--];
                else
                    nums1[k--] = nums2[j--];
            } 
            else if(i < 0) {
                nums1[k--] = nums2[j--];
            }
            else if(j < 0) {
                nums1[k--] = nums1[i--];
            }
        }
    }
}