def add(x, y):
    return x + y

def subtract(x, y):
    return x - y

def multiply(x, y):
    return x * y

def divide(x, y):
    return x / y

print("Select Operation")
print("1.Add")
print("2.Subtract")
print("3.Multiply")
print("4.Divide")

while True:
    choice = input("Enter Your Choice(1/2/3/4):")

    if choice in ('1', '2', '3', '4'):
        num1 = float(input("Enter First Number:"))
        num2 = float(input("Enter Second Number:"))

        if choice == '1':
            res = num1+num2
            print("Ans:",res)

        elif choice == '2':
            res = num1-num2
            print("Ans:",res)

        elif choice == '3':
            res = num1*num2
            print("This is your number:",res)

        elif choice == '4':
            res = num1/num2
            print("This is your number:",res)

print("Multiplication Table")
num = int(input("Choose your number:"))
for i in range(1, 21):
   print(num, 'x', i, '=', num*i)

print("Reverse count")
num = int(input("Choose your number:"))
for i in range(1, 101):
   print(num, '-', i, '=', num-i)