找出数组中只出现一次的两个数字

# include <stdio.h>

int findFirstOne(int num)
{
    int flag = 1;
    int count = 0;
    while (flag)
    {
        if (num & flag == 1)
            break;
        flag << 1;
        count++;
    }
    return count;
}

int isOne(int num,int index)
{
    if ((num & (1<<index)) == 1)
        return 1;
    else
        return 0;
}

void findTwoNumbers(int arr[],int len)
{
    int i = 0;
    int ret = 0;
    int result = 0;
    int num1 = 0;
    int num2 = 0;
    for (i = 0;i < len; i++)
    {
        result ^= arr[i];
    }
    ret = findFirstOne(result);
    for (i = 0;i < len;i++)
    {
        if (isOne(arr[i],ret) == 1)
        {
            num1 ^= arr[i];
        }
        else
        {
            num2 ^= arr[i];
        }
    }
    printf ("%d  %d\n",num1,num2);
}

int main()
{
    int arr[] = {1,2,5,2,4,3,3,1};
    int len = sizeof (arr)/sizeof (arr[0]);
    findTwoNumbers(arr,len);
    return 0;
}