Function Problems....

i get a bunch of errors with my mult func. being at the top and i forgot how to make functions properly how do i fix this?

Code:

---

#include <iostream>
#include <cstdlib>

using namespace std;
 
int a;
int b;
int c;

void voided() {
cout << "doesnt return anythin so im void" << endl;
}

void mult(a, b);

int main()
{
    cout << "4 + 6 IS "<< mult(4, 6) <<"!" << endl;
    cout << "void function "<< voided <<"" << endl;
    system("PAUSE");
    return 0;
}
mult(a, b) {
a + b = c; //a plus the value of be assigns the answer to c
return c; // gives the answer ex if a is 2 and b is 3 it would return 5
}

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Well for one you've declared mult to return nothing (void), but then proceed to return c. And you forgot to include the return type in the second declaration.

>void mult(a, b);
If you want your function to return a value then declare it so:

Code:

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int mult(int a, int b);

---

And your assignment statement is backwards.

?????

i tried to make it not bein void but says it must be declared nd that mult is not declared/defined

and i thought that was how u made a prototype function

Quote:

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Originally Posted by swoopy

And your assignment statement is backwards.

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Haha I didn't even notice that one. :D

Seriously, get yourself a good book. You seem to lack the understanding of even the simplest concepts like functions, so it's going to be really hard to learn anything from the seemingly random tutorials on the web.

lol no! i used to know em really well then i started API and forgot it lol

Eh... That last statement makes no sense at all.

Anyway, an example:

Code:

---

// Good...
int foo(int x);

int main { ... }

int foo(int x)
{
  return 1;
}

// Bad...
int foo(int x);

int main { ... }

int foo(/* nothing here */ x)
{
  return 1;
}

// Also bad...
int foo( );

int main { ... }

/* nothing here */ foo( )
{
  return 1;
}

---

The signature of the function for both declaration and definition must match exactly*. And, C++ is strongly typed; all variables must have a type.

* This excludes the parameter names (and only the names). So, the following are fine:

Code:

---

void foo(int x);
void foo(int fred)
{
  cout << fred; // **not** cout << x;
}

void bar(int);
void bar(int y)
{
  cout << y;
}

---

Cheers

you didn't assign a type for your function such as int mult() .for your function, you don't need to declare the variables first.

Code:

---

//you can write it like this

double mult( double a, double b ){

return a*b;

}


//then in your main function you can simply write

int main(){

cout << "4 x 5 IS " << mult(4,5);

return 0;

}

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in my example, all you need to do is pass the values into the function, and instead of creating a variable to hold the product of 4 and 5, you simply return it.

i remembered while doin my classes lol ty all