LeetCode之Remove Duplicates from Sorted Array II

1、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.

2、代码实现

public class Solution {

   public int removeDuplicates(int[] nums) {

    if (null == nums || nums.length == 0) {

     return 0;

    }

    int length = nums.length;

    int newLen = 1;

    int count = 1;

    for (int i = 1; i < length; ++i) {

     if (nums[i] == nums[i - 1]) {

      count++;

      if (count <= 2) {

       nums[newLen++] =  nums[i];

      }

     } else {

      count = 1;

      nums[newLen++] = nums[i];

     }

       return newLen;

   }

}

3、总结

既然看到连续相等，那我们就要想到前后两个不相等作为条件，然后加上通过一个变量不超过2个就可以了