java数组去重

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.

解法如下：

public class Solution {
    public int removeDuplicates(int[] nums) {
        if(nums==null)
            return 0;
        if(nums.length==1)
            return 1;
        int current = 0;
        int next = 1;
        int len = nums.length;
        while(next<len){
            if(nums[next]==nums[current]){
                for(int j=next;j<len-1;j++){
                    nums[j] = nums[j+1];
                }
                len--;
            }
            if(nums[next]!=nums[current]){
                next++;
                current++;
            }

        }
        return len;
    }
}