LeetCode

题目：

Follow up for "Remove Duplicates":
What if duplicates are allowed at most twice?

For example,
Given sorted array nums = [1,1,1,2,2,3],

Your function should return length = 5, with the first five elements of nums being 1, 1, 2, 2 and 3. It doesn't matter what you leave beyond the new length.

思路：

向前多判断一步

package array;

public class RemoveDuplicatesFromSortedArrayII {

    public int removeDuplicates(int[] nums) {
        int len = 0;
        if (nums == null || (len = nums.length) < 2) return len;
        int start = 1;
        for (int i = 2; i < len; ++i) {
            if (nums[i] != nums[start] || nums[start] != nums[start - 1])
            {    
                ++start;
                nums[start] = nums[i];
            }
        }
        return start + 1;
    }
    
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        int[] nums = { 1,1,1,2,2,3 };
        RemoveDuplicatesFromSortedArrayII r = new RemoveDuplicatesFromSortedArrayII();
        System.out.println(r.removeDuplicates(nums));
    }

}