help me ! some declaration error

i got this error ISO C++ forbids declaration of 'VolymCube' with no type .. i think i wrote exactly same as the book ( C++ for beginner in 3 weeks) but the program dont work here is the code.

Code:

---

#include <iostream>

int VolymCube ( int lenght, int width = 25, int height = 1);
using namespace std;
int main ()

{
   
    int lenght = 100;
    int width = 50;
    int height = 25;
    int volym;
   
    volym = VolymCube( lenght,width,height);
    cout << " Volym first round is " << volym << "\n";
   
   
    volym = VolymCube( lenght,width);
    cout << " Volym second round is " << volym << "\n";
   
   
    volym = VolymCube( lenght);
    cout << " Volym third round is " << volym << "\n";
   
    int z;
    cin >> z;
    return 0;
   
}

VolymCube (int lenght, int width, int height)

{
          return ( lenght * width * height);
         
          }

---

what is the error you get?

So take a look at the line where the error is and see how it differs from how you have declared the function earlier?

You're declared the function as returning int. When defining (implementing) the function you have not specified the return type.

its working now thax for got to put int infront of VolymCube