class Solution {
    public int removeDuplicates(int[] nums) {

        int n = nums.length;
        if(0==n) {
            return 0;
        }
        int de = 1;
        int mov = 1;
        while(mov < n) {

            if(nums[mov] != nums[mov - 1]) {

                nums[de] = nums[mov];
                de++;
            }
            mov++;
        }
        return de;
     
    }
}