leetcode: 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 A = [1,1,2],

Your function should return length = 2, and A is now [1,2].

先統計出有多少重複的數，然後用兩個指針就可以原地排了

class Solution {
public:
    int removeDuplicates(int A[], int n) {
        if( n < 2)
            return n;
        int cnt = 0;
        int cur = INT_MIN;
        for( int i = 0; i < n; ++i){
            if( cur == A[i]){
                ++cnt;
                continue;
            }
            else
                cur = A[i];
        }
        cur = INT_MIN;
        for( int i = 0, j = 0; i < n - cnt; ++j){
            if( cur == A[j])
                continue;
            else{
                cur = A[j];
                A[i++] = A[j];
            }
        }
        return n - cnt;
    }
};