from sys import stdin, stdout
input = lambda: stdin.readline().rstrip()
write = stdout.write

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

    if not A % 10 and not B % 10:
        ans = (A * B) // 10
    else:
        ans = A * B
        if not -99999999 <= ans <= 99999999:
            ans = 'E'
    print(ans)

main()