I can't seem to understand the bug in this code

[ammar629]

Write a function that takes 3 integer parameters and returns the maximum value.

  #include <iostream>
#include <conio.h>
#include <iomanip>


void max (int,int,int);
using namespace std;
int main() {
int x,y,z;
int q;

cout << "Enter Three Integer Values " << endl;
cin >> x >> y >> z;
  q = max (x,y,z);
  cout << q;
}


max (int &a,int &b,int &c)
{
    if (a>b && a>c) {
        cout << a;

    }
    else if (b>a && b>c) {
        cout << b;
    }
    else {
        cout << c;

    }

}

[keskiverto]

 In function 'int main()':
14:5: error: void value not ignored as it ought to be

 At global scope:
19:26: error: ISO C++ forbids declaration of 'max' with no type [-fpermissive]

 In function 'int max(int&, int&, int&)':
33:1: warning: no return statement in function returning non-void [-Wreturn-type] 

and returns the maximum value

Line 6: Function max returns void -- no value.
Line 14: you cannot store void into int q;

Line 19: If max is a function, what is its return type? There is nothing before name "max".

Line 33: Due to line 19 error the compiler decided that return type is int. Alas, the function does not return any value.

[adam2016]

keskiverto explains it above

but yeah you are missing void,your prototype is not the same as the declaration

a function must return something if it does not it should return void.

also your function should return an int

because you cannot set an int = to void max returns void so return an int

also in your prototype you have three ints but it should be three int references

here is the fixed up code

#include <iostream>


using namespace std;
int max(int&,int&,int&); // error was here

int main() {
int x,y,z;
int q;

cout << "Enter Three Integer Values " << endl;
cin >> x >> y >> z;
 q = max(x,y,z); // error was here
  cout << q;
}


int max(int &a,int &b,int &c)
{
    if (a>b && a>c) {
        cout << a;
        return a; // error here
    }
    else if (b>a && b>c) {
        cout << b;
        return b;
    }
    else {
        cout << c;
        return c;
    }

}

hope that helps

[keskiverto]

Now questions on logic:

* If the main() receives and "answer" to q and then prints the answer,
why does the max() print anything?

* Why does the function take references?
Does it need to modify caller's variables?
Could you ever call q = max( x, y, 0 );?