leetcode 排序数组去重复并返回新数组长度Remove Duplicates from Sorted Array

Given a sorted array, 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 in place with constant memory.
For example,
Given input array 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 new length.

本数组已经排序好数组，不仅仅要返回去重后长度，也要实现去重：

一开始思路：

假定数组nums在0-j之内无重复，则从j+1-numsize-1之中任意一个元素i与(0-j)比较，如都不相同则num[j+1]=num[i]

int removeDuplicates1(int* nums, int numsSize) {  int i,j=0,k;int l=numsSize;for(i=1;i<numsSize;i++){   k=0;   while(k<=j&&nums[k]!=nums[i])k++;   if(k>j)nums[++j]=nums[i];  }numsSize=j+1;   return numsSize;}

后来发现时间复杂度过大o(n^2)

改变思路，利用已经排好序，相同的则是相连的：

int removeDuplicates(int* nums, int numsSize){int k=0;int i;for(i=1;i<numsSize;i++)  {if(nums[i]!=nums[i-1])nums[i-k]=nums[i];  else k++; }return numsSize-k;}