136. Single Number

  public static int singleNumber(int[] nums) {        Arrays.sort(nums);        int count = 0;        int  i = 0;        while(i < nums.length){            if(i == 0 || nums[i] == nums[i-1]) {                count++;                i++;            }else{                if(count == 1) {                    if(i < nums.length) {                        return nums[i-1];                    }else {                        return nums[i];                    }                }else{                    count = 1;                    i+=1;                }            }        }        return count == 0 ?nums[0]:nums[i-1];    }