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The greater number

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Join Date: Mar 2007

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nottoshabi nottoshabi is offline

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The greater number

Mar 10th, 2007

It works. I'm having a problem trying to display the greater number
to the output. For example what ever number is greater the
first or the second it still displays the first number.
Couse that is what is coded in the cout. But I dont know
what to put in it to display the greater number instead
of the fisrt number. Also I dont know how to connect the fisrt part of the code to the second. For example the void block of code is completlly independent of the main. The program will run the same with the void function in or out.

 Help with Code Tags 
 c Syntax (Toggle Plain Text) 
 
#include <iostream>
using namespace std;
 
 
void Max(int& x, int& y)
{                    // start of function body
  int max; 
  int other;       // variable declaration
 
  if (x >= y) 
  {       // find the maximum number
    max = x;
  }
  else
  {
    (x <= y);
 
    max = y;
  }
 
}
 
 
int main()
{
  void Max( int& , int&);  // function declaration (prototype)
  int firstnum, secnum;
 
  cout << "\nEnter a number: ";
  cin  >> firstnum;
  cout << "Great! Please enter a second number: ";
  cin  >> secnum;
 
  cout << "\nThe maximum of these two values is "
       << firstnum << endl; // the function is 
                                             //called here
 
  system("PAUSE");
  return 0;
}
#include <iostream>
using namespace std;


void Max(int& x, int& y)
{                    // start of function body
  int max; 
  int other;       // variable declaration

  if (x >= y) 
  {       // find the maximum number
    max = x;
  }
  else
  {
    (x <= y);
    
    max = y;
  }

}


int main()
{
  void Max( int& , int&);  // function declaration (prototype)
  int firstnum, secnum;

  cout << "\nEnter a number: ";
  cin  >> firstnum;
  cout << "Great! Please enter a second number: ";
  cin  >> secnum;

  cout << "\nThe maximum of these two values is "
       << firstnum << endl; // the function is 
                                             //called here

  system("PAUSE");
  return 0;
}

Last edited by WaltP; Mar 11th, 2007 at 3:07 pm. Reason: Fixed: 'language' means the language you are using -- like C or CPP...

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John A

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Re: The greater number

Mar 10th, 2007

Your function's prototype should not be inside another function, as your are doing here. It should also be BEFORE the function definition.

Change the function's return type from void to int. The return the value of 'max'. All that's necessary is for you to call the function in the cout call, and the value will be printed out.

By the way, how come you declare the variable 'other' when you don't have any use for it?

"Technological progress is like an axe in the hands of a pathological criminal."

All my posts may be freely redistributed under the terms of the MIT license.

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Infarction Infarction is offline

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Re: The greater number

Mar 10th, 2007

you should just output the maximum of the two:

 Help with Code Tags 
 C++ Syntax (Toggle Plain Text) 
cout << "the max is " << max(firstnum, secondnum)) << endl;
cout << "the max is " << max(firstnum, secondnum)) << endl;

that said, your max function is wrong. It finds the max but should return the result. Here's a cleaner version:

 Help with Code Tags 
 C++ Syntax (Toggle Plain Text) 
int max(int a, int b)
{
  if(a > b)
    return a;
  else
    return b;
}
int max(int a, int b)
{
  if(a > b)
    return a;
  else
    return b;
}

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John A

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Re: The greater number

Mar 10th, 2007

•

Originally Posted by joeprogrammer

All that's necessary is for you to call the function in the cout call, and the value will be printed out.

•

Originally Posted by Infarction

you should just output the maximum of the two:
Help with Code Tags

C++ Syntax (Toggle Plain Text)
cout << "the max is " << max(firstnum, secondnum)) << endl;
cout << "the max is " << max(firstnum, secondnum)) << endl;

That's what I meant to say. Really. :o

"Technological progress is like an axe in the hands of a pathological criminal."

All my posts may be freely redistributed under the terms of the MIT license.

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nottoshabi nottoshabi is offline

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Re: The greater number

Mar 10th, 2007

I will try to switch that around. About the other I dont know. I'm new to this. It all looks like chinese to me right now. I get the code from the professor I just need to tweek it to his specifications. If you ask me why I do certain things i dont know. thats what i'm trying to figure out.

Thanks for the help guys.

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WaltP

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Re: The greater number

Mar 11th, 2007

•

Originally Posted by Infarction

Here's a cleaner version:
Help with Code Tags

C++ Syntax (Toggle Plain Text)
int max(int a, int b)
{
  if(a > b)
    return a;
  else
    return b;
}
int max(int a, int b) { if(a > b) return a; else return b; }

Except multiple returns from a single function is frowned upon. Best to keep your original function with the return changes mentioned above, and with one other minor change:

 Help with Code Tags 
 c Syntax (Toggle Plain Text) 
if (x >= y) 
{       // find the maximum number
    max = x;
}
else
{
//    (x <= y);    remove this line, it does nothing
    max = y;
}
if (x >= y) 
{       // find the maximum number
    max = x;
}
else
{
//    (x <= y);    remove this line, it does nothing
    max = y;
}

Last edited by WaltP; Mar 11th, 2007 at 3:14 pm.

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1) Never do today that which can be put off until tomorrow
2) Tomorrow never comes

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~s.o.s~

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Re: The greater number

Mar 11th, 2007

•

Originally Posted by WaltP

Except multiple returns from a single function is frowned upon.

Hmm...now that is some news

The statement is not absolute as such. It all depends on the problem under consideration.

Last edited by ~s.o.s~; Mar 11th, 2007 at 4:15 pm.

I don't accept change; I don't deserve to live.

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Infarction Infarction is offline

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Re: The greater number

Mar 11th, 2007

•

Originally Posted by WaltP

Except multiple returns from a single function is frowned upon.

That's more a matter of style for ease of maintenance, AFAICT. IMHO, this function is more clear this way, though if you want a single return, it could be done as

 Help with Code Tags 
 C++ Syntax (Toggle Plain Text) 
int max(int a, int b) {
  return (a > b ? a : b);
}
int max(int a, int b) {
  return (a > b ? a : b);
}

but I didn't want to post that one for clarity's sake.

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WaltP

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Re: The greater number

Mar 12th, 2007

•

Originally Posted by ~s.o.s~

The statement is not absolute as such. It all depends on the problem under consideration.

Which is why I stated it as I did -- not as an absolute.

•

Originally Posted by Infarction

That's more a matter of style for ease of maintenance, AFAICT. IMHO, this function is more clear this way, though if you want a single return, it could be done as
Help with Code Tags

C++ Syntax (Toggle Plain Text)
int max(int a, int b) {
  return (a > b ? a : b);
}
int max(int a, int b) { return (a > b ? a : b); }
but I didn't want to post that one for clarity's sake.

Very good choice!!

Purists frown on multiple returns. They can be harder to debug because sometimes a return gets lost in complex or long functions. IMO, you should try to use only one return point if the code to support it does not make the code overly complex. But don't make the code difficult to read to accomplish it.

For this piece of code I'd probably use:

 Help with Code Tags 
 c Syntax (Toggle Plain Text) 
int max(int a, int b)
{
    int rtn = a;
    if(a < b)  rtn = b;
    return rtn;
}
int max(int a, int b)
{
    int rtn = a;
    if(a < b)  rtn = b;
    return rtn;
}

The 3 Laws of the Procrastination Society:
1) Never do today that which can be put off until tomorrow
2) Tomorrow never comes

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Re: The greater number

#10

Mar 12th, 2007

I guess it will depend on the coding standards of the company you are working for. Here are two implementations of the function which finds the index of an element in the array and returns -1 if not found.

 Help with Code Tags 
 c Syntax (Toggle Plain Text) 
// MULTIPLE RETURNS
 
int indexOf2 (int array[], int length, int element)
{
    for (int i = 0; i < length; ++i)
    {
        if (array [i] == element)
            return i ;
    }
    return -1 ;
}
 
// SINGLE RETURN
 
int indexOf1 (int array[], int length, int element)
{
    int index = -1 ;
 
    for (int i = 0; i < length; ++i)
    {
        if (array [i] == element)
        {
            index = i ;
            break ;     // btw even break and continue are frowned upon
        }
    }
    return index ;
}
// MULTIPLE RETURNS

int indexOf2 (int array[], int length, int element)
{
    for (int i = 0; i < length; ++i)
    {
        if (array [i] == element)
            return i ;
    }
    return -1 ;
}

// SINGLE RETURN

int indexOf1 (int array[], int length, int element)
{
    int index = -1 ;

    for (int i = 0; i < length; ++i)
    {
        if (array [i] == element)
        {
            index = i ;
            break ;     // btw even break and continue are frowned upon
        }
    }
    return index ;
}