Performing Calculation

Part of the Fundamentals section of Coddy's Dart journey. Lesson 90 of 94.

Challenge

Easy

Now that we have two numbers and an operation, we can perform the calculation.

Update your calculator program to:

Create a variable named result with type double? (nullable double) to store the result of the calculation
Use if-else statements to perform the appropriate calculation based on the operation:
- If operation is '+', set result to firstNumber + secondNumber
- If operation is '-', set result to firstNumber - secondNumber
- If operation is '*', set result to firstNumber * secondNumber
- If operation is '/', check if secondNumber is 0
If attempting division by zero, print exactly: "Error: Cannot divide by zero!" and use the return statement to exit the function
For all valid calculations, set the result variable appropriately
Print "Result: " followed by the result value

Try it yourself

void main() {
  print("Welcome to the Simple Calculator!");
  
  // Declare and initialize number variables
  double firstNumber = 10.5;
  double secondNumber = 5.5;
  
  // Print the numbers
  print("First number: $firstNumber");
  print("Second number: $secondNumber");
  
  // Declare and validate the operation variable
  String operation = "*";  // Can be +, -, *, or /
  
  // Check if operation is valid
  if (operation != '+' && operation != '-' && operation != '*' && operation != '/') {
    print("Invalid operation. Using addition (+) as default.");
    operation = '+';
  }
  
  print("Operation: $operation");
  
  // Perform the calculation here
}