Print the numbers of form (2^i)*(5^j) in increasing order

Print the numbers of form (2^i)*(5^j) in increasing order, e.g. 1, 2, 4, 5, 8, 10, 16, 20, …

Q：题目很简单了，就是打印整数序列，该序列的生成规则为(2^i)*(5^j)

 

void Compute_Increasing_Order() 
{
    int arr[20] = {0};
    arr[0]= 1; printf("%d, ", arr[0]);
    int count_2 = 0;
    int count_5 = 0;
    for(int i = 1; i <= 10 ; i++)
    {
        // 将(2^i)*(5^j)转化为2*arr[count_2] 或者 5*arr[count_5]
        if(2 * arr[count_2] <= 5 * arr[count_5])
        {
            arr[i] = 2 * arr[count_2];
            count_2 ++;

            // 该句是保证2 * arr[count_2] == 5 * arr[count_5] 相等时，
// count_2 and count_5都必须+1，否则，会出现重复
            if (2 * arr[count_2] == 5 * arr[count_5]) count_5++; 
        } 
        else 
        {
            arr[i] = 5 * arr[count_5];
            count_5 ++; 
        }

        printf("%d, ", arr[i]);
    }

    cout << endl;
}