#calculator

import math

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):
    if y == 0:
        return "Error! Division by zero."
    return x / y

def floor_divide(x, y):
    if y == 0:
        return "Error! Division by zero."
    return x // y

def modulo(x, y):
    if y == 0:
        return "Error! Division by zero."
    return x % y

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

def logarithm(x):
    return math.log(x)

def square_root(x):
    return math.sqrt(x)

def sine(x):
    return math.sin(x)

def cosine(x):
    return math.cos(x)

def calculator():
    while True:
        print("Options:")
        print("Enter '+' for addition")
        print("Enter '-' for subtraction")
        print("Enter '*' for multiplication")
        print("Enter '/' for division")
        print("Enter '//' for floor division")
        print("Enter '%' for modulo")
        print("Enter '^' for exponentiation")
        print("Enter 'log' for logarithm")
        print("Enter 'sqrt' for square root")
        print("Enter 'sin' for sine")
        print("Enter 'cos' for cosine")
        print("Enter 'q' to quit")

        choice = input("Enter choice: ")

        if choice == 'q':
            break

        if choice not in ['sqrt', 'sin', 'cos']:
            num1 = float(input("Enter first number: "))
            if choice != '^':
                num2 = float(input("Enter second number: "))

        if choice == '+':
            print("Result:", add(num1, num2))
        elif choice == '-':
            print("Result:", subtract(num1, num2))
        elif choice == '*':
            print("Result:", multiply(num1, num2))
        elif choice == '/':
            print("Result:", divide(num1, num2))
        elif choice == '//':
            print("Result:", floor_divide(num1, num2))
        elif choice == '%':
            print("Result:", modulo(num1, num2))
        elif choice == '^':
            print("Result:", exponential(num1, num2))
        elif choice == 'log':
            print("Result:", logarithm(num1))
        elif choice == 'sqrt':
            print("Result:", square_root(num1))
        elif choice == 'sin':
            print("Result:", sine(num1))
        elif choice == 'cos':
            print("Result:", cosine(num1))
        else:
            print("Invalid input")

calculator()