x = float(input())
y = float(input())
operation = input()

if ((operation == '/' or
     operation == 'mod' or
     operation == 'div') and y == 0):
    print('Деление на 0!')
else:
    if operation == '+':
        print(x + y)
    elif operation == '-':
        print(x - y)
    elif operation == '/':
        print(x / y)
    elif operation == '*':
        print(x * y)
    elif operation == 'mod':
        print(x % y)
    elif operation == 'pow':
        print(x ** y)
    elif operation == 'div':
        print(x // y)
    else:
        print('ввели что-то странное, я бы тут очень ругался')