Hey guys i m trying to do an assignment that was posted about 10-15years ago. but i m doing it with a slight bit of modification. Below is the detail of the assignment.

http://www.taumoda.com/web/class/day6.html


What i am trying to do is, instead of it being a kids b'day party, let it be a normal adults party.

Let there be x number of invited guests. and lets imagine that 50% of all the guest consumer beer. and let beer come in kegs to feed 20 guests/keg.

I just need help with the last function in my code. where i want the number of invited guest to come from an earlier function (inv_guest) and then calculate the number of kegs of beer to be ordered. for example, if 123 people are invited, a total of 4 kegs of beer will be ordered; 3 for the first 60 and an extra 1 for the remaining 1 person.

Code:
#include <iostream>
#include <stdlib.h>
using namespace std;

const int kegs = 20;
const int cases = 20;
const int pizza = 4;
int num_guest = 0;

void welcome();
int inv_guest(int);
void display();
void input();
void beer(int &);
void coke();
int main ()
{
    int x, choice;
    
   
   /* 
    while (choice!=6)
    {
     switch(choice)
*/
    input();
    
    
    beer(num_guest);
 
 
 
 system("PAUSE");
 return 0;   
};

void input()
{

     int choice;
     welcome();  
do 
{
   
   cout<<"\n\nEnter A Valid Choice \n";
   cin>>choice;
}while(!(choice>=1 && choice<=5));

}

int inv_guest(int num_guest)
{
    int guest;
    
    cin >> guest;
 return guest;   
}

void welcome()
{
          cout << "\t***The Party Planning Assistant is please to be at your service!***\n\n";
          cout<<"\n*********************************\n";
          cout<<" 1. Enter number of Invited Guests \n";
          cout<<" 2. Determine beverage orders \n";
          cout<<" 3. Determine food orders \n";
          cout<<" 4. Display Information \n";
          cout<<" 5. Exit Application \n";
          cout<<"***********************************"; 
 
     
}
void beer(int &people)
{
     double beer = 0;
     people *= inv_guest(people);;
    // inv_guest(people);
     beer = people/2;
     beer = beer/kegs
     cout << "\n\n Number of kegs =" << kegs;
     
}