https://oj.leetcode.com/problems/single-number-ii/

Single Number II.java

public class Solution {
    public int singleNumber(int[] A) {
        int[] count = new int[32];
        int result = 0;
        for (int i = 0; i < 32; i++) {
            for (int j = 0; j < A.length; j++) {
                if (((A[j] >> i) & 1) == 1) {
                    count[i]++;
                }
            }
            result |= ((count[i] % 3) << i);
        }
        return result;
    }
}