https://leetcode.com/problems/remove-duplicates-from-sorted-array/
class Solution { public: int removeDuplicates(vector<int>& nums) { if (nums.size()==0) return 0; int front=0; for (int i=1; i<nums.size();++i) { if (nums[front]!=nums[i]) { front++; nums[front]=nums[i]; } }
return front+1; } };