A number appears 2 times, and the rest of the numbers appear 3 times.

a large array full of numbers, except that one of the numbers appears 2 times, and the remaining numbers appear 3 times. How do I find the number that only happened two times?
Among them, ones recorded that all the Bit,twos records that appeared 3 and 1 times were the remaining 2. Not_threes is when a bit appears for the 3rd time, clear it off.

Public classtest3in2 {/**     * @paramargs*/     Public Static voidMain (string[] args) {//TODO auto-generated Method Stub        intOnes=0; intTwos=0; intNot_threes=0; inta[]={22,33,22,66,66,33,33,66,55,22,55,55,121,121};  for(inti=0;i<a.length;i++) {twos|=ones&A[i]; Ones^=A[i]; Not_threes=~ (ones&twos); Ones&=not_threes; Twos&=not_threes; } System.out.println ("222====" +twos); System.out.println ("111====" +ones); }}

A number appears 2 times, and the rest of the numbers appear 3 times.