def formposicaodig(x):
    '''
    How many digits are there up to the first digit of x
    (x-10^(n-1))*n + [sum 9*(10^(k-2))*(k-1), from k = 2 to n]
    = (x-10**(n-1))*n + n * 10**(n-1) + (1 - 10**n)//9
    '''
    n = len(str(x))

    return 1 +  (x-10**(n-1))*n + n * 10**(n-1) + (1 - 10**n)//9

def formInvposicaodig(pos):
    '''
    x = The position digit 'pos' is contained in which number
    n = len(str(x)) : Number of digits in x
    x = ( pos + (10**n  -1)//9 - n * 10**(n-1) -1) / n + 10**(n-1) 
    return : What is the nth digit of Champernowne's constant
    '''
    n = len(str(pos))
    xcalc = (pos + (10**n-1)//9 - 1) // n
    # As I don't know the number of digits of x, 
    # I iterate until the xcal found is equal to the size of the formula to determine it.
    while n != len(str(xcalc)):
        n = len(str(xcalc))
        xcalc = (pos + (10**n-1)//9 - 1) // n
    return int(str(xcalc)[pos - formposicaodig(xcalc)])


n = int(input())
for k in range(n):
    prd = 1
    for j in map(int,input().split()):
        nth = formInvposicaodig(j)
        if nth == 0:
            prd = 0
            break
        else:
            prd *= nth
    print(prd)