Problem:
 Score : 100 points    Problem Statement Having learned the multiplication table, Takahashi can multiply two integers between 1 and 9 (inclusive) together. He cannot do any other calculation.  Given are two integers A and B .  If Takahashi can calculate A \times B , print the result; if he cannot, print -1 instead.      Constraints  1 \leq A \leq 20  1 \leq B \leq 20  All values in input are integers.         Input Input is given from Standard Input in the following format:  A  B       Output If Takahashi can calculate A \times B , print the result; if he cannot, print -1 .        Sample Input 1 2 5      Sample Output 1 10  2 \times 5 = 10 .       Sample Input 2 5 10      Sample Output 2 -1  5\times 10 = 50 , but Takahashi cannot do this calculation, so print -1 instead.       Sample Input 3 9 9      Sample Output 3 81

Solution (Python):
a,b=input().split()
a=int(a)
b=int(b)
if 0<a<10 and 0<b<10:
  print(a*b)
else:
  print('-1')

Solution (Python):
A, B = map(int, input().split(" "))

if A < 10 and B < 10:
  print(A * B)
else:
  print(-1)

Solution (Python):
a, b = map(int, input().split())
if a <= 9 and b <= 9:
    print(a * b)
else:
    print("-1")

Solution (Python):
a, b = map(int, input().split())
if a <= 9:
    if b <= 9:
        print(a * b)
    else:
        print("-1")
else:
    print("-1")

Solution (Python):
a,b=map(int,input().split())
print(a*b if max(a,b)<10 else -1)

Solution (Python):



A, B = map(int, input().split())

print(A * B if (A < 10 and B < 10) else -1)

Solution (Python):
import sys
input = sys.stdin.readline
a,b=[int(j) for j in input().split()]
if a<10 and b<10:
    print(a*b)
else:
    print(-1)

Solution (Python):
a,b = map(int,input().split())
if(a<10 and b<10):
  print(a*b)
else:
  print("-1")

Solution (Python):
A,B = map(int,input().split())
if A <= 9 and B <= 9:
    print(A*B)
else:
    print(-1)

Solution (Python):

A, B = map(int, input().split())
if A // 10 == 0 and B // 10 == 0:
    print(A * B)
else:
    print(-1)

Solution (Python):
a, b = map(int, input().split())

if (a >= 10) or (b >= 10):
    print('-1')
else:
    print(a * b)

Solution (Python):
a, b = map(int, input().split())

if 1<=a<=9 and 1<=b<=9:
	print(a*b)
else:
	print(-1)

Solution (Python):
a,b = map(int, input().split())
print(a*b if a<=9 and b<=9 else -1)

Solution (Python):
a,b = map(int, input().split())
if a<=9 and b <=9:
  print(a*b)
else:
  print(-1)

Solution (Python):
a,b=list(map(int,input().strip().split()))
if a<=9 and b<=9:
    print(a*b)
else:
    print(-1)

Solution (Python):
A, B = map(int, input().split())
if A > 9 or B > 9:
    print(-1)
else:
    print(A * B)

Solution (Python):
a, b = map(int, input().split())

if a <= 9 and b <= 9:
    print(a*b)
else:
    print("-1")

Solution (Python):
a,b=map(int,input().split())
if(a<10 and b<10):
  print(a*b)
else:
  print(-1)

Solution (Python):
a,b=map(int, input().split())
if (1 <= a and a <= 9) and (1<= b and b <= 9):
    print(a*b)
else:
    print(-1)

Solution (Python):
A, B = map(int, input().split())
if A <= 9 and A >= 1 and B <= 9 and B >= 1:
    print(A * B)
else:
    print(-1)

Solution (Python):
a, b = map(int, input().split(' '))

if a > 9 or b > 9:
    print('-1')
    exit()
print(a * b)

Solution (Python):
A, B = map(int, input().split())

if A < 10 and B < 10:
    print(A * B)
else:
    print('-1')

Solution (Python):
a, b = [int(n) for n in input().split(' ')]

if 1>a or a>9 or 1>b or b>9:
    print(-1)
else:
    print(a*b)

Solution (Python):
A, B = map(int, input().split())

if 1 <= A <= 9 and 1 <= B <= 9:
    print(A*B)
else:
    print(-1)

Solution (Python):
A, B = map(int, input().split())
if A > 9 or B > 9:
  print("-1")
else:
  print(A * B)

Solution (Python):
a,b = map(int,input().split())

if a > 9 or b > 9:
    print('-1')
else:
    print(a*b)

Solution (Python):
a,b=map(int,input().split())
if a>=10 or b>=10:
  print(-1)
else:
  print(a*b)

Solution (Python):
inp = input()
a = inp.split(" ")[0]
b = inp.split(" ")[1]
if(len(a)==1 and len(b)==1):
  print(int(a)*int(b))
else:
  print("-1")

Solution (Python):
a, b = map(int, input().split())

if 10 <= a or 10 <= b:
    print(-1)
    exit()

else:
    print(a*b)

Solution (Python):
a,b = map(int,input().split())

if (a >= 10) or (b >= 10):
  print(-1)
else:
  print(a*b)

Solution (Python):
A, B = tuple(map(int, input().split()))
if 10 <= A or 10 <= B:
    print(-1)
else:
    print(A * B)

Solution (Python):
A, B = map(int, input().split())
ans = A * B if A <= 9 and B <= 9 else -1

print(ans)

Solution (Python):
A, B = map(int, input().split())
flag = 0
if not 1<=A<=9:
    flag = 1
if not 1<=B<=9:
    flag = 1
if flag == 0:
    print(A*B)
else:
    print(-1)

Solution (Python):
x = (input().split())
a = int(x[0])
b = int(x[1])

if 0 < a < 10 and 0 < b < 10:
    print(a*b)
else:
    print('-1')

Solution (Python):
a,b=list(map(int,input().split(' ')))
if(a>=1 and a<=9 and b>=1 and b<=9):
  print(a*b)
else:
  print(-1)

Solution (Python):
a, b = map(int, input().split())

if a <= 9 and b <= 9:
  print(a*b)
else:
  print(-1)

Solution (Python):
def math(A, B):
    if A < 10:
      if B < 10:
        result = A*B
      else:
        result = -1
    else:
      result = -1
    return result
 
A, B = map(int,input().split())
result1 = math(A, B)
print(result1)

Solution (Python):
a,b=map(int,input().split())
if a<=9 and b<=9:
  print(a*b)
else:
  print(-1)

Solution (Python):
a, b = map(int, input().split())
if 1 <= a <= 9:
  if 1 <= b <= 9:
    print(a * b)
    exit()
    
print(-1)

Solution (Python):
A,B = map(int,input().split())

if A <= 9:
  if B <= 9:
    x = A*B
  else:
    x = -1
else:
  x = -1

print(x)

Solution (Python):
a,b=map(int,input().split())
if a>9 or b>9:
  print(-1)
else:
  print(a*b)

Solution (Python):
A,B=map(int,input().split())

if A<=9 and B<=9:
    x=A*B
else:
    x=-1

print(x)

Solution (Python):
a,b = map(int,input().split())
if 0<a<=9 and 0<b<=9:
    print(a*b)
else:
    print(-1)

Solution (Python):
A, B = map(int, input().split())
if A >= 10 or B >= 10:
  print(-1)
else:
  print(A*B)

Solution (Python):

A, B = map(int, input().split())
if (A//10) + (B//10):
    ans = -1
else:
    ans = A * B
print(ans)

Solution (Python):
a, b = [int(c) for c in input().split()]

if 1 <= a <= 9 and 1 <= b <= 9:
  print(a * b)
else:
  print(-1)

Solution (Python):


a, b = map(int, input().split())
if 1 <= a <= 9 and 1 <= b <= 9:
    print(a * b)
else:
    print(-1)

Solution (Python):
A, B = map(int, input().split())
if A < 10 and B < 10:
    print(A*B)
else:
    print(-1)

Solution (Python):
A,B=map(int,input().split())

if A>=1 and A<=9 and B>=1 and B<=9:
  print(A*B)
else:
  print(-1)

Solution (Python):
A,B = map(int,input().split())
if( ( 0 <= A and A < 10 ) and ( 0 <= B and B < 10) ):
    print(A*B)
else:
    print(-1)

Solution (Python):
A, B = map(int, input().split())
if len(str(A)) == 1 and len(str(B)) == 1:
    print(A * B)
else:
    print(-1)

Solution (Python):
a, b = map(int, input().split())

if a >= 10 or b >= 10:
    print(-1)
else:
    print(a * b)

Solution (Python):
A,B=map(int,input().split())
if A<10 and B<10:
    print(A*B)
else:
    print(-1)

Solution (Python):
a, b = map(int, input().split())
print(a*b if a <= 9 and b <= 9 else -1)

Solution (Python):
a, b = map(int, input().split(" "))
if a >= 10 or b >= 10:
    print(-1)
else:
    print(a*b)

Solution (Python):
a,b = input().split()
a=int(a)
b=int(b)
if a<10 and b<10:
    ans=a*b
    print(ans)
else:
    print('-1')

Solution (Python):
a, b = map(int, input().split())

if a > 9 or b > 9:
    print(-1)
    exit()

print(a * b)

Solution (Python):
a, b = map(int, input().split())
if a>=10 or b>=10:
    print(-1)
else:
    print(a*b)

Solution (Python):
a, b = map(int, input().split())
print(a*b) if (1 <= a and a < 10) and (1 <= b and b < 10) else print(-1)

Solution (Python):
A, B = (int(x) for x in input().split())

if 0<A and A<10 and 0<B and B<10:
    print(A*B)
else:
    print(-1)

Solution (Python):
A,B = map(int,input().split())

if (0 <= A and A < 10) and ( 0 <= B and B < 10):
    print(A*B)
else:
    print(-1)

Solution (Python):

import sys


def solve(A: int, B: int):
    print(A * B if A <= 9 and B <= 9 else -1)



def main():
    def iterate_tokens():
        for line in sys.stdin:
            for word in line.split():
                yield word
    tokens = iterate_tokens()
    A = int(next(tokens))  
    B = int(next(tokens))  
    solve(A, B)

if __name__ == '__main__':
    main()

Solution (Python):

from collections import defaultdict,deque
from heapq import heappush, heappop
from bisect import bisect_left, bisect_right
import sys, random, itertools, math
sys.setrecursionlimit(10**5)
input = sys.stdin.readline
sqrt = math.sqrt
def LI(): return list(map(int, input().split()))
def LF(): return list(map(float, input().split()))
def LI_(): return list(map(lambda x: int(x)-1, input().split()))
def II(): return int(input())
def IF(): return float(input())
def LS(): return list(map(list, input().split()))
def S(): return list(input().rstrip())
def IR(n): return [II() for _ in range(n)]
def LIR(n): return [LI() for _ in range(n)]
def FR(n): return [IF() for _ in range(n)]
def LFR(n): return [LI() for _ in range(n)]
def LIR_(n): return [LI_() for _ in range(n)]
def SR(n): return [S() for _ in range(n)]
def LSR(n): return [LS() for _ in range(n)]
mod = 1000000007
inf = float('INF')


def A():
    a, b = LI()
    def c(x):
        return 1 <= x <= 9
    if c(a) and c(b):
        print(a * b)
        return
    print(-1)
    return


def B():
    a = set()
    for i in range(10):
        for k in range(10):
            a.add(i * k)
    x = II()
    if x in a:
        print("Yes")
    else:
        print("No")
    return


def C():
    n = II()
    factlize = []
    ans = inf
    for i in range(1, int(sqrt(n)) + 1):
        if n % i == 0:
            ans = min(ans, n // i + i - 2)
    print(ans)

    return


def D():
    a, b, x = LI()
    from math import atan

    return


def E():
    def solve(m):
        a1 = a[::-1]
        f1 = f[::1]
        res = 0
        for i in range(n):
            if a1[i] * f1[i] <= m:
                continue
            k = m // f1[i]
            res += a1[i] - k
            if res > K:
                return False
        return True

    n, K = LI()
    a = LI()
    a.sort()
    f = LI()
    f.sort()
    ok = max(a) * max(f)
    ng = -1
    while ok - ng > 1:
        mid = (ok + ng) // 2
        if solve(mid):
            ok = mid
        else:
            ng = mid
    print(ok)
    return


def F():
    return



if __name__ == '__main__':
    A()

Solution (Python):
A,B = map(int, input().split(" "))
if A <= 9 and B <= 9:
  print(A*B)
else:
  print(-1)

Solution (Python):
A,B = map(int,input().split())
if A < 10 and B < 10:
    print(A*B)
else:
    print(-1)

Solution (Python):
data = list(map(int,input().split()))
a = data[0]
b = data[1]

if 1<=a<=9 and 1<=b<=9:
  print(a*b)
else:
  print(-1)

Solution (Python):
import sys

def main():
    A, B = map(int, input().split())

    if(1<=A<=9 and 1<=B<=9):
        print(A*B)
    else:
        print('-1')

main()

Solution (Python):
L=list(map(int, input().split()))
A=L[0]
B=L[1]

ans=0
if A<=9:
    if B<=9:
        ans=A*B
    else:
        ans=-1
else:
    ans=-1

print(ans)

Solution (Python):
A,B = map(int,input().split())
ans = A*B

if A<=9 and B<=9:
    print(ans)
else :
    print(-1)

Solution (Python):
a,b=map(int,input().split())

if 1<=a<=9 and 1<=b<=9:
    print(a*b)
else:
    print(-1)

Solution (Python):
a,b=(int(x) for x in input().split())

if 0<a and a<10 and 0<b and b<10:
    print(a*b)
else:
    print("-1")

Solution (Python):
a, b = map(int, input().split())
if 1 <= a <= 9 and 1 <= b <= 9:
    print(a * b)
else:
    print('-1')

Solution (Python):
a,b=map(int,input().split())
print((-1,a*b)[a<10 and b<10])

Solution (Python):
a,b = map(int,input().split())

if a >= 10 or b >= 10:
  print(-1)
else:
  print(a*b)

Solution (Python):
a,b = map(int, input().split())
if a <= 9 and b <= 9:
  print(a*b)
else:
  print(-1)

Solution (Python):
A,B=input().split()
A=int(A)
B=int(B)

if A>9 or B>9:
  print(-1)
else:
  print(A*B)

Solution (Python):
x,y = list(map(int,input().split()))
if x < 10 and y < 10:
	print(x*y)
else:
  print('-1')

Solution (Python):
a,b = map(int,input().split())

if 1 <= a and a <= 9:
    if 1 <= b and b <= 9:
        print(a*b)
    else:
        print("-1")
else:
    print("-1")

Solution (Python):
a,b=map(int,(input().split()))
if a>= 10:
  print(-1)
elif b>= 10:
  print(-1)
else:
  print(a*b)

Solution (Python):
a=input()
b=a.split()
if int(b[0])<10 and int(b[1])<10:
    print(int(b[0])*int(b[1]))
else:
    print("-1")

Solution (Python):
A,B = map(int , input().split()) 
if A > 9 or B > 9:
    print(-1)
else:
    print(A*B)

Solution (Python):
a,b  = map(int, input().split())
if a<=9 and b<=9 :
    print(a*b)
else :
    print(-1)

Solution (Python):
a, b = input().split()
a, b = int(a), int(b)

if max(a, b) > 9:
  print(-1)
else:
  print(a * b)

Solution (Python):
usrInput = input()
splitedInput = usrInput.split()
clearFlag = []

for i in range(2):
    if int(splitedInput[i]) < 10:
        clearFlag.append(True)
    else:
        clearFlag.append(False)

if bool(clearFlag[0]) == True and bool(clearFlag[1]) == True:
    print(int(splitedInput[0]) * int(splitedInput[1]))
else:
    print(-1)

Solution (Python):
a,b=map(int,input().split());print(a*b if a-9<1and b-9<1else-1)

Solution (Python):
a,b=map(int, input().split());print(a*b if a-9<1and b-9<1else -1)

Solution (Python):
A, B = input().split()

if int(A) <= 9 and int(B) <= 9 and int(A) >= 1 and int(B) >= 1:
    print(int(A) * int(B))
else:
    print(-1)

Solution (Python):
a, b = map(int, input().split())

if a >= 10 or b >= 10:
    print(-1)
else:
    print(a*b)

Solution (Python):
i = list(map(int, input().split()))
 
A=i[0] 
B=i[1] 

if A<=9 and B<=9:
  print(A*B)
else:
  print(-1)

Solution (Python):
def main():
    a, b = map(int, input().split())

    print(a*b if a<=9 and b <= 9 else -1)


if __name__ == '__main__':
    main()

Solution (Python):
A,B =map(int,input().split())

if 1<= A <=9 and 1<= B <=9:
    print(A*B)
else :
    print(-1)

Solution (Python):
n,m=map(int,input().split())
if 1<=n<=9 and 1<=m<=9:
    print(n*m)
else:
    print(-1)

Solution (Python):
A, B = map(int, input().split())

if A <= 9 and B <= 9:
  print(A*B)
else:
  print(-1)

Solution (Python):
a,b = map(int,input().split())
if a <= 9 and b <= 9:
  print(a*b)
else:
  print(-1)

Solution (Python):
A, B = list(map(int, input().split(" ")))
if not A >9 and not B >9:
    print(A*B)
else:
    print("-1")

Solution (Python):
x,y = map(int,input().split())
if x<=9 and y<=9:
    print(x*y)
else:
    print(-1)

Solution (Python):
n=input()
n=n.split()
a=int(n[0])
b=int(n[1])

if(a>=10 or b>=10):
    ans=-1
else:
    ans=a*b
    
print(ans)

Solution (Python):
a, b = input().split()
if len(a) > 1 or len(b) > 1:
    print("-1")
else:
    print(int(a) * int(b))

Solution (Python):


A, B = map(int, input().split())

if A<=9 and B<=9:
    print("{}".format(A*B))
else:
    print("{}".format(-1))

Solution (Python):
x,y=map(int,input().split())
if x<=9 and y<=9:
  print(x*y)
else:
  print(-1)

Solution (Python):
a,b = map(int,input().split())
if a<10 and a>0 and b<10 and b>0:
    ans = a * b
    print(ans)
else:
    print(-1)

Solution (Python):
l=list(map(int,input().split()))
a=l[0]
b=l[1]
if(a<=9 and b<=9):
  print(a*b)
else:
  print(-1)

Solution (Python):
a,b = map(int, input().split())
if len(str(a)) == 1 and len(str(b)) == 1:
  print(a*b)
else:
  print(-1)

Solution (Python):
a, b = map(int, input().split())
if a < 10 and b < 10:
    print(a * b)
else:
    print(-1)

Solution (Python):
IN = input().split()
X, Y = int(IN[0]), int(IN[1])

if len(str(X)) == 1 and len(str(Y)) == 1:
  print(X*Y)
else:
  print(-1)

Solution (Python):
a,b=map(int,input().split())
print(a*b if a<10 and b<10 else "-1")

Solution (Python):
a,b=map(int,input().split())
if 0<a<10 and 0<b<10:
    print(a*b)
else:
    print(-1)

Solution (Python):
A,B = (int(i) for i in input().split())

if A <= 9 and B <= 9:
    print(A * B)
else:
    print(-1)

Solution (Python):
a,b = input().split()

if int(a) >9 or int(b)>9:
   ret = -1
else:
   ret = int(a)*int(b)
print(ret)

Solution (Python):
A,B = map(int,input().split())

if A > 9 or B > 9:
	print(-1)
else:
	print(A*B)

Solution (Python):
a,b = map(int,input().split())
if a <= 9 and b <= 9:
    print(a*b)
else:
    print(-1)

Solution (Python):
a, b = map(int, input().split())

if a > 9 or b > 9:
    print("-1")
else:
    print(a*b)

Solution (Python):
a, b = map(int,input().split())
print(a*b if a < 10 and b < 10 else -1)

Solution (Python):
a,b=map(int,input().split())
if a<10 and b<10:
  print(a*b)
else:
  print(-1)

Solution (Python):
list = input().split(" ")
if int(list[0]) >= 10 or int(list[1]) >= 10:
  print("-1")
else:
  sum = int(list[0])*int(list[1])
  print(sum)

Solution (Python):
A,B= map(int, input().split())


if 1<=A<=9 and 1<=B<=9:
	print(A*B)
else:
  	print(-1)

Solution (Python):

A,B = map(int,input().split())
if A <= 9 and B <= 9:
    print(A*B)
else:
    print(-1)

Solution (Python):
a,b = map(int,input().split())

if  1<=a<=9 and 1<=b<=9:
    print(a*b)
else:
    print(-1)

Solution (Python):
A,B=map(int,input().split())
print(A*B if A<10and B<10else'-1')

Solution (Python):
a, b = map(int, input().split())
if a >= 1 and a <= 9 and b >= 1 and b <= 9:
  print(a*b)
else:
  print(-1)

Solution (Python):
A, B = input().split()
A = int(A)
B = int(B)
if A < 10 and B < 10 :
  print(A * B)
else:
  print(-1)

Solution (Python):
a = list(int(x) for x in input().split())
if 1 <= a[0] <= 9 and 1 <= a[1] <= 9:
  print(a[0]*a[1])
else:
  print(-1)

Solution (Python):
r = lambda: map(int, input().split(' '))
x,y = r()
if x > 9 or y > 9:
  print(-1)
else:
  print(x*y)

Solution (Python):
A,B=map(int,input().split())
if A<=9 and B<=9:
  print(A*B)
else:
  print(-1)

Solution (Python):
a, b = map(int, input().split())
if a <= 9 and b <= 9:
  print(a*b)
else:
  print(-1)

Solution (Python):
input_list = list(map(int, input().split()))
a = input_list[0]
b = input_list[1]

if (1 <= a <= 9) & (1 <= b <= 9):
    print(a*b)
else:
    print(-1)

Solution (Python):
a, b = map(int, input().split())
if 1<= a <= 9 and 1<= b <= 9:
    print(a*b)
else:
    print(-1)

Solution (Python):
A,B=input().split()
A=int(A)
B=int(B)

if 0<A<10 and 0<B<10:
    print(A*B)
else:
    print(-1)

Solution (Python):
a,b =map(int,input().split())

if a<10 and b <10:
	print(a*b)
else:
	print('-1')

Solution (Python):
n = list(map(int, input().split()))
a = n[0]
b = n[1]

if a < 10 and b <10:
  print(a*b)
else:
  print(-1)

Solution (Python):
A ,B = map(int, input().split())
List = [1,2,3,4,5,6,7,8,9]
if (A in List) and (B in List):
  print(A*B)
else:
  print(-1)

Solution (Python):
a,b=map(int,input().split())
if 1<=a<=9 and 1<=b<=9:
  print(a*b)
else:
  print(-1)

Solution (Python):
def main():
    
    a, b = map(int, input().split())
    
    if a < 10:
        if b < 10:
            print(a*b)
            return
    
    print(-1)

main()

Solution (Python):
a,b = map(int,input().split())
if a<10 and b<10:
  print(a*b)
else:
  print("-1")

Solution (Python):

[A, B] = [int(i) for i in input().split(" ")]
if (1 <= A <= 9) and (1 <= B <= 9):
    print(A*B)
else:
    print(-1)

Solution (Python):
a, b = map (int, input().split())
if a<10 and b<10:
  print(a*b)
else:
  print('-1')

Solution (Python):
A, B = map(int,input().split())
 
if 1<= A <= 9 and 1 <= B <= 9:
    print(A*B)
    exit()
 
print(-1)

Solution (Python):
a,b = map(int,input().split())

if a>9 or b>9 :
  print('-1')
  
else :
  print(a*b)

Solution (Python):



def main():
    a, b = map(int, input().split())

    if a <= 9 and b <= 9:
        print(a * b)
    else:
        print(-1)


if __name__ == '__main__':
    main()

Solution (Python):
A, B = map(int, input().split())
if (A<=9) and (B<=9):
    print(A*B)
else:
    print(-1)

Solution (Python):
A, B = map(int, input().split())
if 0 <= A <= 9 and 0 <= B <= 9:
    print(A*B)
else:
    print(-1)

Solution (Python):
class Takahashi:
  def __init__(self, a , b):
    self.a = a
    self.b = b
    
  def test(self):  
    if self.a <10 and self.b <10:
      return a * b
    else:
      return '-1'
    
a, b = list(map(int,input().split(' ')))

keisan = Takahashi(a,b)
ans = keisan.test()
print(ans)

Solution (Python):
A,B=map(int,input().split())
if 1 <= A <= 9 and 1 <= B <= 9:
    print(A*B)
else:
    print(-1)

Solution (Python):
x,y=map(int,input().split())
if x>9 or y>9:
  print(-1)
  exit(0)
else:
  print(x*y)

Solution (Python):
a, b = map (int, input().split())

if a < 10 and b < 10:
  print (a*b)

else:
  print (-1)

Solution (Python):
A, B = map(int, input().split())

if A<10 and B<10:
    print(A*B)
else:
    print(-1)

Solution (Python):
a, b = map(int, input().split())

if a <= 9 and b <= 9:
    print(a*b)
else:
    print(-1)

Solution (Python):
a,b = map(int,input().split())
if a<10 and b<10:
  print(a*b)
else:
  print(-1)

Solution (Python):

from collections import defaultdict, Counter
from itertools import product, groupby, count, permutations, combinations
from math import pi, sqrt
from collections import deque
from bisect import bisect, bisect_left, bisect_right
from string import ascii_lowercase
from functools import lru_cache
import sys
sys.setrecursionlimit(10000)
INF = float("inf")
YES, Yes, yes, NO, No, no = "YES", "Yes", "yes", "NO", "No", "no"
dy4, dx4 = [0, 1, 0, -1], [1, 0, -1, 0]
dy8, dx8 = [0, -1, 0, 1, 1, -1, -1, 1], [1, 0, -1, 0, 1, 1, -1, -1]


def inside(y, x, H, W):
    return 0 <= y < H and 0 <= x < W


def ceil(a, b):
    return (a + b - 1) // b


def sum_of_arithmetic_progression(s, d, n):
    return n * (2 * s + (n - 1) * d) // 2


def gcd(a, b):
    if b == 0:
        return a
    return gcd(b, a % b)


def lcm(a, b):
    g = gcd(a, b)
    return a / g * b


def solve():
    return


def main():
    A, B = map(int, input().split())
    if 1 <= A <= 9 and 1 <= B <= 9:
        print(A * B)
    else:
        print(-1)


if __name__ == '__main__':
    main()

Solution (Python):
a, b = input().split(' ')

if int(a) >= 10 or int(b) >= 10:
    print('-1')
else:
    print(int(a)*int(b))

Solution (Python):
a,b=map(int,input().split())
if(a>=10):
    print(-1)
elif(b>=10):
    print(-1)
else:
    print(a*b)

Solution (Python):








import sys

A,B=list(map(int,input().strip().split()))

if A>9 or B>9:
    print(-1)
    sys.exit()
else:
    print(A*B)

Solution (Python):
a,b = map(int,input().split())
if a < 10 and b < 10:
  print(a * b)
else:
  print(-1)

Solution (Python):
x, y = map(int, input().split())

if x > 9 or y > 9:
  print(-1)
else:
  print(x * y)

Solution (Python):
a, b = map(int, input().split())

if a > 9 or b > 9:
    print(-1)
else:
    print(a * b)

Solution (Python):
A,B = map(int,input().split())
if A<10 and B<10:
  print(A*B)
else :
  print("-1")

Solution (Python):
a,b = map(int,input().split())
if 1<=a<=9 and 1<=b<=9:
    print(a*b)
else:
    print(-1)

Solution (Python):
inputs = list(map(int, input().split()))
a = inputs[0]
b = inputs[1]

if a < 10 and b < 10:
  print(a*b)
else:
  print(-1)

Solution (Python):
a, b = map(int, input().split())
if a > 9 or b > 9:
    print(-1)
else:
    print(a * b)

Solution (Python):
A, B = map(int, input().split(" "))
if 1 <= A <= 9 and 1 <= B <= 9:
    print(A * B)
else:
    print("-1")

Solution (Python):

A_str, B_str = input().split()
A, B = int(A_str), int(B_str)

if 1 <= A <= 9 and 1 <= B <= 9:
  print(A*B)
else:
  print(-1)

Solution (Python):
a,b = map(int,input().split())
if a >= 10 or b >= 10:
  print(-1)
else:
  print(a*b)

Solution (Python):
a,b=map(int,input().split())
if 1<=a<=9 and 1<=b<=9:
  print(a*b)
else:
  print(-1)

Solution (Python):
a, b = map(int, input().split())
if 1<=a<=9 and 1<=b<=9: print(a*b)
else: print(-1)

Solution (Python):
a,b = map(int, input().split())
if a < 10 and b < 10:
    print(a*b)
else:
    print(-1)

Solution (Python):
x,y = map(int,input().split())
import sys

if x>9 or y>9:
    print(-1)
else:
    print(x*y)

Solution (Python):
a,b = map(int,input().split())
if a>9 or b>9:
  print(-1)
else:
  print(a*b)

Solution (Python):
a,b=(int(x) for x in input().split())
if a < 10 and b < 10:
    ans = a * b
else:
    ans = -1
print(ans)

Solution (Python):
A, B = map(int, input().split())
print(A * B if A <= 9 and B <= 9 else -1)

Solution (Python):
a,b = map(int,input().split())
if a > 9 or b > 9:
  print(-1)
else:
  print(a * b)

Solution (Python):
a, b = map(int,input().split())
if(a > 9 or b > 9):
	print("-1")
else:
	print(a * b)

Solution (Python):
a, b = map(int, input().split())

if a >= 10 or b >= 10:
    print(-1)
else:
    print(a * b)

Solution (Python):
a, b = [int(i) for i in input().split(" ")]

if (a < 10 and a > 0) and (b < 10 and b > 0):
    print(a * b)
else:
    print(-1)

Solution (Python):

if __name__ == '__main__':

	A = list(map(int,input().split()))

	if (1 <= A[0] <= 9) and (1 <= A[1] <= 9):
		print(A[0] * A[1])
	else:
		print(-1)

Solution (Python):
x,y=map(int,input().split())

if x>=10 or y>=10:
  print("-1")
else:
  print(x*y)

Solution (Python):
a,b =  (int(x) for x in input().split())
if a<10 and b<10:
    print (a*b)
else:
    print('-1')

Solution (Python):
a,b = [int(_) for _ in input().split()]
if a<10 and b<10:
    print(a*b)
else:
    print(-1)

Solution (Python):
a = list(map(int, input().split()))
if(a[0] < 10 and a[1] < 10):
    print(a[0]*a[1])
else:
    print('-1')

Solution (Python):
x,y =map(int,input().split())

if x > 9:
    print(-1)

elif y > 9:
    print(-1)

else:
    print(x*y)

Solution (Python):
a,b=map(int,input().split())
print(a*b if a<10 and b<10 else -1)

Solution (Python):
ab_list = input().split(' ')
a = int(ab_list[0])
b = int(ab_list[1])
if a <= 9 and b <= 9:
  print(a*b)
else:
  print(-1)

Solution (Python):
num_array = [int(s) for s in input().split(" ")]

can_calc_nums = list(filter(lambda x: 1 <= x and x <= 9, num_array))
answer = -1
if len(can_calc_nums) == 2:
	answer = can_calc_nums[0] * can_calc_nums[1]

  
print(answer)

Solution (Python):
A,B = map(int,input().split())
if 1 <= A and A <= 9 :
    if 1 <= B and B <= 9 :
        print(A*B)
    else :
        print(-1)
else :
    print(-1)

Solution (Python):
a, b = map(int, input().split())
if a <= 9 and b <= 9:
    print(a*b)
else:
    print(-1)

Solution (Python):
a,b = map(int , input().split())
if(a < 10 and b < 10):
  print(a * b)
else :
  print(-1)

Solution (Python):
import sys

def main():
    
    a, b = map(int,input().split())
    if (a > 9) or (b > 9):
    	print (-1)
    else:
    	print(a * b)
    

if __name__ == '__main__':
	main()

Solution (Python):
S = input()
li = S.split(" ")
A = int(li[0])
B = int(li[1])
if A>9 or B>9:
    print(-1)
else:
    print(A*B)

Solution (Python):

import sys














def main():
    a, b = [int(x) for x in sys.stdin.readline().split()]
    print(-1 if a >= 10 or b >= 10 else a * b)

if __name__ == "__main__":
    main()

Solution (Python):
a,b = map(int , input().split())

if a > 9 or a < 1:
	print(-1)
elif b > 9 or b < 1:
	print(-1)
else:
	print(a*b)

Solution (Python):
list = input().split(' ')
A = int(list[0])
B = int(list[1])
if A <= 9 and B <= 9:
    print(A*B)
else:
    print(-1)

Solution (Python):
a,b=map(int,input().split())
if (1<=a<=9) and (1<=b<=9):
    print(a*b)
else:
    print(-1)

Solution (Python):
A, B = (int(x) for x in input().split(' '))
if A <= 9 and B <= 9:
    print(A*B)
else:
    print(-1)

Solution (Python):
line_str = input().split()

a = int(line_str[0])
b = int(line_str[1])

if 1 <= a <=9 and 1 <= b <=9:
    print(a*b)
else:
    print(-1)

Solution (Python):
a, b = list(map(int, input().split(" ")))
if a < 10 and b < 10:
  print(a * b)
else:
  print(-1)

Solution (Python):
a,b = input().strip().split()
a = int(a)
b = int(b)
if a <= 9 and b <= 9:
    print(a*b)
else:
    print(-1)

Solution (Python):

b, c = map(int, input().split())

if b > 9 or c > 9:
    print(-1)
else:
    print(b*c)

Solution (Python):
a,b = map(int,input().split( ))
if (1 <= a <= 9) and (1 <= b <= 9):
  c = a*b
else:
  c = -1
print(c)

Solution (Python):
a,b = (int(i) for i in input().split())
if a<=9 and b<=9:
    print(a*b)
else:
    print(-1)

Solution (Python):
A, B = (int(x) for x in input().split())

if A<=9 and B<=9:
    print(A*B)
else:
    print(-1)

Solution (Python):
A, B = map(int, input().split())
print(A*B if A in range(1, 10) and B in range(1, 10) else -1)

Solution (Python):
a,b=map(int,input().split())
print('{}'.format(a*b if a<10 and b<10 else -1))

Solution (Python):
a,b=map(int,input().split())
print('{}'.format(a*b if a<10 and b<10 else -1))

Solution (Python):
a,b = map(int, input().split())
if a <= 9 and b <= 9:
  print(a*b)
else:
  print(-1)

Solution (Python):
a,b = map(int,input().split())


if(0 < a < 10 and 0< b < 10):
  print(a*b)
  
else:
  print("-1")

Solution (Python):
ar=list(map(int,input().split()))
if ar[1]<10 and ar[0]<10:
  print(ar[0]*ar[1])
else:
  print(-1)

Solution (Python):
A, B = map(int, input().split())

if A < 10 and B < 10:
  print(A * B)
else:
  print(-1)

Solution (Python):
A, B = map(int, input().split())

if 1 <= A <= 9 and 1 <= B <= 9:
  print(A * B)
else:
  print(-1)

Solution (Python):
a, b = map(int, input().split())
ans = -1
if a < 10 and b < 10:
    ans = a * b
print(ans)

Solution (Python):
A, B = map(int, input().split())
print(A*B if A<10 and B<10 else -1)

Solution (Python):
x,y=map(int,input().split())
if x >= 10 or y >= 10:
  print(-1)
else:
  print(x * y)

Solution (Python):
a,b = map(int,input().split())
if 1<=a<=9 and 1<=b<=9:
  print(a*b)
else:
  print(-1)

Solution (Python):
a,b = map(int, input().split())

if a >9 or b > 9:
    print("-1")
else:
    ans = a * b
    print(ans)

Solution (Python):
import re
A,B = input().split(' ')
if len(A) == 1 and len(B) == 1:
    print(int(A)*int(B))
else:
    print(-1)

Solution (Python):
A, B = map(int, input().split())
ans = -1
if A < 10:
    if B < 10:
        ans = A*B
print(ans)

Solution (Python):
A, B = map(int, input().split())
if A < 10 and B < 10:
  print(A * B)
else:
  print(-1)

Solution (Python):
a,b = map(int,input().split())
if a>9 or b>9:
    print(-1)
else:
    print(a*b)

Solution (Python):
a, b = map(int, input().split())

answer = 0
 
if a >= 10 or b >= 10:
  answer = -1
else:
  answer = a * b
  
print(answer)

Solution (Python):
a,b=map(int, input().split())
print(a*b if a < 10 and b < 10 else -1)

Solution (Python):
a, b=map(int, input().split())
if a<=9 and b <=9:
  print(a*b)
else:
  print(-1)

Solution (Python):
a,b=map(int,input().split())
print(a*b if a<10 and b<10else "-1")

Solution (Python):
a, b= map(int,input().split())

if 1<=a<10 and 1<=b<10:
  print(str(a*b))
else:
  print(str(-1))

Solution (Python):
a, b = map(int, input().split())
if 1 <= a <= 9 and 1 <= b <= 9:
    print(a*b)
else:
    print(-1)

Solution (Python):
A, B = map(int, input().split())
if A <= 9 and B <= 9:
    print(A*B)
else:
    print(-1)

Solution (Python):
A,B = map(int, input().split())

if A>=10 or B>=10:
    print(-1)
else:
    print(A*B)

Solution (Python):
A=input().split()
a,b=int(A[0]),int(A[1])
if a<10 and b<10:
    print(a*b)
else :print(-1)

Solution (Python):
A, B = map(int, input().split())
if (1 <= A <= 9) and (1 <= B <= 9):
    print(A * B)
else:
    print(-1)

Solution (Python):
A,B = input().split(" ")
A = int(A)
B = int(B)

if 1 <= A <= 9 and 1 <= B <= 9:
  print(A * B)
else:
  print(-1)

Solution (Python):
def judge(a,b):
  if a<10 and b<10:
    print(a*b)
  else:
    print(-1)

a,b = map(int,input().split())
judge(a,b)

Solution (Python):
a,b=map(int,input().split())

print(a*b if 1<=a<=9 and 1<=b<=9 else -1)

Solution (Python):
a,b=map(int,input().split())
print(a*b if a<10 and b<10 else -1)