【Leet Code】26. Remove Duplicates from Sorted Array---Easy

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.

思路：

相当于设两个指针，一个指示下面的值应该插入的位置，另一个指示下一个需要比较的值的位置。因为数组是有序的，所以相同元素肯定是连续存储的，所以对于相同元素只需要存储一次就够了。

代码实现：

class Solution {public:    int removeDuplicates(int A[], int n) {        if(n <= 0) return 0;       int j = 0, i = 1;        while(i < n)       {           while(A[i] == A[j]) i++;           if(i < n)           {               j++;               A[j] = A[i];           }       }       return j+1;    }};