1. [删除排序数组中的重复项](https://leetcode.com/problems/remove-duplicates-from-sorted-array/) - 用两个指针来维护 - 和快排的partition中维护i和j差不多的意思 ```js var removeDuplicates = function(nums) { let i = 0; let j = 1; while(j < nums.length) { if(nums[j] !== nums[i]) { nums[++i] = nums[j]; } j++; } return i + 1; }; ```