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