Slide 2 > num; power = pow ( num, 2 ); cout > num1
>> num2; m"> num2 ) result = num1; else result = num2;
return result; } // function prototype (function declaration) //
function heading function definition // function call 5">
Example: MAX of 2 numbers #include using namespace std; int Max
( int num1, int num2 ); int main() { int num1, num2, maxResult; cin
>> num1 >> num2; maxResult = Max ( num1, num2 );
cout
Review: Element of a function int Max ( int num1, int num2 ) {
int result; if ( num1 > num2 ) result = num1; else result =
num2; return result; } Return Data TypeFunction NameParameter List
Function Body 6
Slide 7
Function Prototype C++ programmer usually place all supporting
functions after the main function. C++ rule: identifiers must be
declared before use! Place a function prototype before the main
function as a declaration. Two ways to declare a function: int max
( int num1, int num2 ); OR int max ( int, int ); 7 Add a semicolon
to the function heading, and you get the function prototype!
Slide 8
Function Prototype #include using namespace std; int max ( int
num1, int num2 ); int main() { maxResult = max ( num1, num2 ) } int
max ( int num1, int num2 ) { int result; if ( num1 > num2 )
result = num1; else result = num2; return result; } #include using
namespace std; int max ( int num1, int num2 ) { int result; if (
num1 > num2 ) result = num1; else result = num2; return result;
} int main() { maxResult = max ( num1, num2 ) } = 8 Common Practice
!
Slide 9
Review: Two Types of Functions Void Function Return data type
is void Dont need a return statement in the function Function call
format: functionName(parameters); Value-Return Function Return data
type is some real data type ( int, float, string ) Need a return
statement to return a value to the caller function Function call
format: var = functionName(parameters); OR use
functionName(parameters) as a variable. 9
Slide 10
Formal parameters vs. Actual parameters (Arguments) Formal
parameters appears in a function heading. int max ( int num1, int
num2 ); Used in the callee function. Actually parameters
(Arguments) appear in a function call. result = max ( 2, 3 );
During a function call, an argument can be a literal, variable, or
expression. result = pow( 3, 2 ); result = fabs ( num ); result =
sqrt ( num / 2 + 1 ); A function is not required to have arguments.
eof(); Used in the caller function. 10
24 Example: Using a flag float DoIt(int num, char op); int
main() { int base; float result; char choice; cout > base; cout
> choice; while (choice != C && choice != S) { cout >
choice; } result = DoIt(base, choice); cout
25 Example: Using a flag int DoIt(int num, char op); int main()
{ int base; float result; char choice; cout > base; cout >
choice; while (choice != C && choice != S) { cout >
choice; } result = DoIt(base, choice); cout