# Write your Python code here
print("Hello, Excelrs!")
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 calculator():
                                  print("Select Operation:")
                                      print("1. Add (+)")
                                          print("2. Subtract (-)")
                                              print("3. Multiply (*)")
                                                  print("4. Divide (/)")

                                                      while True:
                                                              choice = (
                                                                          input("\nEnter choice (1/2/3/4) or 'q' to quit: ").strip().lower()
                                                                                  )

                                                                                          if choice == "q":
                                                                                                      print("Exiting calculator. Goodbye!")
                                                                                                                  break

                                                                                                                          if choice in ("1", "2", "3", "4"):
                                                                                                                                      try:
                                                                                                                                                      num1 = float(input("Enter first number: "))
                                                                                                                                                                      num2 = float(input("Enter second number: "))
                                                                                                                                                                                  except ValueError:
                                                                                                                                                                                                  print("Invalid input. Please enter numerical values.")
                                                                                                                                                                                                                  continue

                                                                                                                                                                                                                              if choice == "1":
                                                                                                                                                                                                                                              print(f"{num1} + {num2} = {add(num1, num2)}")
                                                                                                                                                                                                                                                          elif choice == "2":
                                                                                                                                                                                                                                                                          print(f"{num1} - {num2} = {subtract(num1, num2)}")
                                                                                                                                                                                                                                                                                      elif choice == "3":
                                                                                                                                                                                                                                                                                                      print(f"{num1} * {num2} = {multiply(num1, num2)}")
                                                                                                                                                                                                                                                                                                                  elif choice == "4":
                                                                                                                                                                                                                                                                                                                                  result = divide(num1, num2)
                                                                                                                                                                                                                                                                                                                                                  print(f"{num1} / {num2} = {result}")
                                                                                                                                                                                                                                                                                                                                                          else:
                                                                                                                                                                                                                                                                                                                                                                      print("Invalid input. Please choose 1, 2, 3, 4, or 'q'.")


                                                                                                                                                                                                                                                                                                                                                                      if __name__ == "__main__":
                                                                                                                                                                                                                                                                                                                                                                          calculator()