Functions

return_type function_name(opt_parameter_list){
    doSomething();
}

• void is no return type
• all other functions must contain a return statement
  • except the main, which returns 0 by default
• arguments are by default passed by value
  • copy of value is taken, which does not alter original
  • see 2.cpp

Unnamed Argument

Absolutely useless, but I guess

int myParamDoesNothing(int){
  return 1;
}
myParamDoesNothing(); // Fails
myParamDoesNothing(123456); //1

Default Argument

int foo(int a, int b = 2, int c = 3){
  return a+b+c;
}
foo(1);//6
foo(1,1);//5
foo(1,1,1)//3

//Cannot do foo(a=4, c=1)