Recap - Simple Calculator

Part of the Object Oriented Programming section of Coddy's GDScript journey. Lesson 8 of 65.

Challenge

Medium

Write the class Calculator in calculator.gd. It keeps a running result in the float property result, which starts at 0.0.

add(number), subtract(number), multiply(number) and divide(number) apply the operation to result with number, store the new result and return it
When divide() gets 0, it prints Error: Division by zero, leaves result unchanged and returns it
clear() sets result back to 0.0 and returns it
get_result() returns result

The supplied code reads how many commands follow, then one command per line, such as add 5, divide 0 or clear. After each command it prints the command name and the value the method returned, and at the end the final result. For add 5, multiply 3, subtract 2, divide 0 and divide 2 it prints:

add -> 5.0
multiply -> 15.0
subtract -> 13.0
Error: Division by zero
divide -> 13.0
divide -> 6.5
Final result: 6.5

Your code goes in calculator.gd. main.gd holds the supplied input/output code and cannot be edited.

Try it yourself

extends Node

func _ready():
	# Supplied input/output code: keep it as it is
	var calc := Calculator.new()
	var count := int(OS.read_string_from_stdin())
	for i in count:
		var parts := OS.read_string_from_stdin().split(" ")
		var value := 0.0
		match parts[0]:
			"add":
				value = calc.add(float(parts[1]))
			"subtract":
				value = calc.subtract(float(parts[1]))
			"multiply":
				value = calc.multiply(float(parts[1]))
			"divide":
				value = calc.divide(float(parts[1]))
			"clear":
				value = calc.clear()
		print("%s -> %s" % [parts[0], value])
	print("Final result: %s" % calc.get_result())