Thread: Functions

Function:

Code:

#include <iostream>
#include <string>

void fry(std::string &food)
{
     std::cout<<"You fried "<<food;
}

int main()
{
    std::string chicken = "Chicken";
    fry(chicken);
    return 0;
}

std::string is the string class provided by C++. I was defining the function if I wanted to prototype it I would have wrote just void fry(std::string &food) and defined it after main(). As for what std::string &food does it is passing the string object itself not a copy so it is "faster" if you wanted you could just write it as void fry(std::string food) and for this function it would produce the same results.

also you can replace the return type (void for the example above) at the begining to something else

Code:

int add(int int1, int int2)  //the int can be replayed with any type
{
return int1 + int2;
}

int main()
{
   cout << add(2,2) << endl;  //this will display 4
   int integer = add(1, 3);  //integer is now 4

return 0;
}

Also you can include <iostream>.

Here is a common way to use functions..

Code:

#include <iostream>
#include <string>

int mult(int x, int y)
{
return x * y;
}

Code:

void fry () 
{
   //put code here
}

void beat ()
{
   //put code here
}

void distort ()
{
   //put code here
}

// Here is where your programs "heart" is... When you run the 
// .exe it starts with the first line from main as you probably know...
// so we can call your functions right here
int main ()
{
   fry ();
   beat ();
   distort ();

   return 0;
}

The void means it has no return type.
A return type is when a function can return a value like lets say your function does 5 + 5 and returns 10 because its the sum. Then you can have a variable like...

"int sum = function(); "
function returns an integer that is assigned to sum.

This will give you a good explanation:
http://www.mvhs.fuhsd.org/bob_vanhoy/pdfs/lesson06.pdf
http://www.mvhs.fuhsd.org/bob_vanhoy/pdfs/lesson07.pdf

You can call your functions multiple times, too.