删除排序数组中的重复项

/*
 * @Author: sumBorn
 * @Date: 2022-02-21 16:13:52
 * @LastEditTime: 2022-02-22 15:00:58
 * @Description: https://leetcode-cn.com/leetbook/read/all-about-array/x9a60t/
 */

/**
 * @description: 双指针，以右侧遍历
 * @param {*}
 * @return {*}
 */
public class Solution
{
    public int RemoveDuplicates(int[] nums)
    {
        if (nums.Length <= 1) return nums.Length;

        int left = 0;
        for (var right = 1; right < nums.Length; right++)
        {
            if (nums[right] != nums[left])
            {
                left++;
                nums[left] = nums[right];
            }
        }

        return ++left;
    }
}

/**
 * @description: old
 * @param {*}
 * @return {*}
 */
public class Solution
{
    public int RemoveDuplicates(int[] nums)
    {
        if (nums.Length == 0) return 0;

        int length = 1;
        int j = 1;
        for (var i = 0; i < nums.Length && j < nums.Length;)
        {
            if (nums[i] == nums[j])
            {
                j++;
            }
            else
            {
                i++;
                nums[i] = nums[j];
                j++;
                length++;
            }
        }

        return length;
    }
}