function problem

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Views: 253 | Replies: 5

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Join Date: Apr 2008

Posts: 2

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info04

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function problem

May 9th, 2008

I am writing a function which will check if the letter is in upper case , if so it returns true otherwise false.
Following is the code, I have written, but what is wrong?

#include<iostream>

using namespace std;

using std::cout;
using std::cin;
using std::endl;

int isUpperCase ( char );

int main()

{
int i;
char c;

cout<<"Enter a charactor : ";
cin>>c;

i = int ( c );

isUpperCase ( i );

return 0;

}

int isUpperCase ( i )

{
if ( i > 65 && i < 90 )

return 1;

else

return 0;

}

please comment.

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Join Date: Aug 2006

Location: Noida, India

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Luckychap

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Re: function problem

May 9th, 2008

Why u are converting a char to int, you can compare char same as u compare int.

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iamthwee

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Re: function problem

May 9th, 2008

How about...

 Help with Code Tags 
 cplusplus Syntax (Toggle Plain Text) 
#include <iostream>
#include <string>
 
using namespace std;
 
class Foo
{
public:
   bool isUpperCase( char t )
   {
     string crap = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
     int size = crap.length();
 
      // check if the same return true 
     //otherwise return false
 
};
 
 
int main()
{ 
  Foo test;
  cout << test.isUpperCase('a') << endl;
 
  cout << test.isUpperCase('A');
 
  cin.get();
}
#include <iostream>
#include <string>

using namespace std;

class Foo
{
public:
   bool isUpperCase( char t )
   {
     string crap = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
     int size = crap.length();
     
      // check if the same return true 
     //otherwise return false

};


int main()
{ 
  Foo test;
  cout << test.isUpperCase('a') << endl;
  
  cout << test.isUpperCase('A');
  
  cin.get();
}

Last edited by iamthwee : May 9th, 2008 at 5:25 am.

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Join Date: Nov 2007

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mitrmkar

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Re: function problem

May 9th, 2008

•

Originally Posted by info04

but what is wrong?

You are excluding the lower and upper bounds, so you could change to

if ( i >= 65 && i <= 90 )

or

if ( i > 64 && i < 91 )

The standard libraries provide functions for checking characters, see e.g. here
http://www.cplusplus.com/reference/clibrary/cctype/

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Join Date: Apr 2008

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tesuji

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Posting Whiz in Training

Re: function problem

May 9th, 2008

hi,
you can also mask bit on position# 6, which is 0 if char is upper case and 1 if char is lower case, e.g. 'A' = 0x41 = 0100 0001 (binary), 'a' = 0x61 = 0110 0001 (binary).

 Help with Code Tags 
 c++ Syntax (Toggle Plain Text) 
bool isUpperCase (char c) {return !(c&0x20);}
. . .
char c='z';
cout<<c<<(isUpperCase(c)?" is upper ":" is lower ")<<"char";
// z is lower char
bool isUpperCase (char c) {return !(c&0x20);}
. . .
char c='z';
cout<<c<<(isUpperCase(c)?" is upper ":" is lower ")<<"char";
// z is lower char

krs,
tesu

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Join Date: Mar 2008

Location: UK

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williamhemswort williamhemswort is offline

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Re: function problem

May 9th, 2008

I see nothing wrong with the function isUpperCase except from what mitrmkar sead, it would not work if you passed the function the characters 'A' or 'Z'.