MonalisaC's calculator.rb

exercise_calculator.rb

@@ -0,0 +1,40 @@
+
+def calculate_answer(operator, a, b)
+  if operator == "add" || operator == "+"
+    return a + b
+  elsif operator == "subtract" || operator == "-"
+    return a - b
+  elsif operator == "multiply" || operator == "*"
+    return a * b
+  elsif operator == "divide" || operator == "/"
+    if b == 0
+      return "divide by zero error!"
+    else return a / b
+    end
+  end
+end
+
+def is_number(num)
+  true if Float(num) rescue false
+end
+
+def get_number(msg)
+  input = ""
+  until is_number(input) do
+    print msg
+    input = gets.chomp
+  end
+  return input.to_f
+end
+
+
+operators = ["add", "+", "subtract", "-", "multiply", "*", "divide", "/"]
+operator_type = ""
+until operators.include? operator_type do
+  print "Please enter operator type (Only the following operators are supported - #{operators.inspect}): #{}"
+  operator_type = gets.chomp
+end
+num1 = get_number ("Enter number 1: ")
+num2 = get_number ("Enter number 2: ")
+answer = calculate_answer(operator_type, num1, num2)
+puts "The answer is #{answer}."