Given a sorted array nums, remove the duplicates in-place such that each element appear only once and return the new length.

Do not allocate extra space for another array, you must do this by modifying the input array in-place with O(1) extra memory.

Example 1:

Given nums = [1,1,2],

Your function should return length = 2, with the first two elements of nums being 1 and 2 respectively.

It doesn't matter what you leave beyond the returned length.

Example 2:

Given nums = [0,0,1,1,1,2,2,3,3,4],

Your function should return length = 5, with the first five elements of nums being modified to 0, 1, 2, 3, and 4 respectively.

It doesn't matter what values are set beyond the returned length.

难度：easy

题目：给定一排序数组，原地移除重复的元素并返回新数组长度且每个元素只出现一次。不要重新分配额外的空间，必须原地修改给出的数组。

思路：用一变量记录置换元素的下标。

Runtime: 6 ms, faster than 99.11% of Java online submissions for Remove Duplicates from Sorted Array.

Memory Usage: 26.6 MB, less than 95.90% of Java online submissions for Remove Duplicates from Sorted Array.

class Solution {    public int removeDuplicates(int[] nums) {        if (nums.length <= 1) {            return nums.length;        }                int idx = 1;        for (int i = 1; i < nums.length; i++) {            if (nums[i] != nums[i - 1]) {                nums[idx++] = nums[i];            }        }                return idx;    }}