‎

What is a function?
What is a return (output)?
What is a parameter (input)?

Keep these examples in your notes:

Function NO INPUT / NO OUTPUT

Function definition example:

Python:

def DisplayMainMenu():
  print( "1. Play game" )
  print( "2. Load game" )
  print( "3. Quit" )

C++:

void DisplayMainMenu()
{
  cout << "1. Play game" << endl;
  cout << "2. Load game" << endl;
  cout << "3. Quit" << endl;
}

Function call example:

Python:

DisplayMainMenu()

C++:

DisplayMainMenu();

Function YES INPUT / NO OUTPUT

Function definition example:

Python:

def Display( name, price ):
  print( "Product:", name, "Price: $", price )

C++:

void Display( string name, float price )
{
  cout << "Product: " << name;
  cout << "Price: $" << price << endl;
}

Function call example:

Python:

product1name = "Burger";
product1price = 7.75
Display( product1name, product1price )

C++:

string product1name = "Burger";
float product1price = 7.75;
Display( product1name, product1price );

Function YES INPUT / YES OUTPUT

Function definition example:

Python:

def Add( num1, num2 ):
  return num1 + num2

C++:

int Add( int num1, int num2 )
{
  return num1 + num2;
}

Function call example:

Python:

number1 = int( input( "Enter first number: " ) )
number2 = int( input( "Enter second number: " ) )
result = Add( number1, number2 )
print( "Result is:", result )

C++:

int number1, number2;
cout << "Enter first number: ";
cin >> number1;
cout << "Enter number 2: ";
cin >> number2;
int result = Add( number1, number2 );
cout << "Result is: " << result << endl;

Function NO INPUT / YES OUTPUT

Function definition example:

Python:

def GetTax():
  return 0.091

C++:

float GetTax()
{
  return 0.091;
}

Function call example:

Python:

tax = GetTax()
total_price = price + price * tax
print( "Total price; $", total_price )

C++:

float tax = GetTax();
total_price = price + price * tax;
cout << "Total price: $" << total_price << endl;