Reversive Array/Integer

[vistatic]

How can i write the coding for a reversive of a given integers.

for example:

char str[] = "012345";

Reverse( str );
printf( str );

then the output will be displayed as "543210"

i need pointer as well to null-terminate string as a parameter and reverses this string. then, the string remains null terminated.

void reverse(char *s)

please help.this is very urgent. thanks.

[meabed]

_strrev, _wcsrev, _mbsrev
Reverse characters of a string.

char *_strrev( char *string );

wchar_t *_wcsrev( wchar_t *string );

unsigned char *_mbsrev( unsigned char *string );

Routine Required Header Compatibility
_strrev Win 95, Win NT
_wcsrev or Win 95, Win NT
_mbsrev Win 95, Win NT

Libraries

LIBC.LIB Single thread static library, retail version
LIBCMT.LIB Multithread static library, retail version
MSVCRT.LIB Import library for MSVCRT.DLL, retail version

Return Value

Each of these functions returns a pointer to the altered string. No return value is reserved to indicate an error.

Parameter

string

Null-terminated string to reverse

Remarks

The _strrev function reverses the order of the characters in string. The terminating null character remains in place. _wcsrev and _mbsrev are wide-character and multibyte-character versions of _strrev. The arguments and return value of _wcsrev are wide-character strings; those of _mbsrev are multibyte-character strings. For _mbsrev, the order of bytes in each multibyte character in string is not changed. These three functions behave identically otherwise.

Security Note These functions incur a potential threat brought about by a buffer overrun problem. Buffer overrun problems are a frequent method of system attack, resulting in an unwarranted elevation of privilege. For more information, see Avoiding Buffer Overruns.
Generic-Text Routine Mappings

TCHAR.H Routine  _UNICODE & _MBCS Not Defined _MBCS Defined _UNICODE Defined 
_tcsrev _strrev  _mbsrev  _wcsrev  


Example

/* STRREV.C: This program checks an input string to
 * see whether it is a palindrome: that is, whether
 * it reads the same forward and backward.
 */

#include <string.h>
#include <stdio.h>

void main( void )
{
   char string[100];
   int result;

   printf( "Input a string and I will tell you if it is a palindrome:\n" );
   gets( string );

   /* Reverse string and compare (ignore case): */
   result = _stricmp( string, _strrev( _strdup( string ) ) );
   if( result == 0 )
      printf( "The string \"%s\" is a palindrome\n\n", string );
   else
      printf( "The string \"%s\" is not a palindrome\n\n", string );
}


Output

Input a string and I will tell you if it is a palindrome:
Able was I ere I saw Elba
The string "Able was I ere I saw Elba" is a palindrome

if u want something else .. i will attach masteringstring.cpp ...

[Dave Sinkula]

Obfuscated for the sake of being too homework-sounding with no work presented.

#include <stdio.h>
 
char *f(char*s){char*t=s,*u=t;while(*u)++u;--u;
while(t<u){char x=*t;*t++=*u;*u--=x;}return s;}
 
int main ( void )
{
   char text[] = "The quick brown fox";
   puts ( text );
   puts ( f ( text ) );
   return 0;
}
 
/* my output
The quick brown fox
xof nworb kciuq ehT
*/

[vistatic]

Actually i was asking about integers, not string char. by given integers 012345, how can i actually reverse it? .....

[Dave Sinkula]

Actually i was asking about integers, not string char. by given integers 012345, how can i actually reverse it? .....

Then this is misleading.i need pointer as well to null-terminate string as a parameter and reverses this string. then, the string remains null terminated.

char str[] = "012345";

Did you think that you couldn't simply change this line?

char text[] = "012345"; /* "The quick brown fox"; */

Did you consider converting an integer to a string, reversing it, and then converting it back to an integer?

But no one is here to do your homework. What coding attempt have you posted? Or do you expect to post homework questions and simply get a correct answer, nicely formatted and commented?

[meabed]

Actually i was asking about integers, not string char. by given integers 012345, how can i actually reverse it? .....

yeah .. i am sorry for this mistake ..
see this example

Summary
An algorithm that reverses the order of elements in a sequence

Synopsis

#include <algorithm>

namespace std {
  template <class BidirectionalIterator>
  void reverse(BidirectionalIterator start,
               BidirectionalIterator finish);
}

Description
The algorithm reverse() reverses the elements in a sequence so that the last element becomes the new first element, and the first element becomes the new last. For each non-negative integer i <= (finish - start)/2, reverse() applies iter_swap() to all pairs of iterators start + I, (finish - I) - 1.

Complexity
reverse() performs exactly (finish - start)/2 swaps.

Example

//
//  reverse.cpp
//

#include <algorithm>   // for reverse, reverse_copy
#include <vector>      // for vector
#include <iostream>    // for cout, endl
#include <iterator>    // for ostream_iterator



int main ()
{
    typedef std::vector<int, std::allocator<int> > Vector;
    typedef std::ostream_iterator<int, char,
                                  std::char_traits<char> >
            Iter;

    // Initialize a vector with an array of integers.
    const Vector::value_type a[] = { 1, 2, 3, 4, 5, 
                                     6, 7, 8, 9, 10 };

    Vector v (a + 0, a + sizeof a / sizeof *a);

    // Print out elements in original (sorted) order.
    std::cout << "Elements before reverse: \n     ";
    std::copy (v.begin (), v.end (), Iter (std::cout, " "));

    // Reverse the ordering.
    std::reverse (v.begin (), v.end ());

    // Print out the reversed elements.
    std::cout << "\n\nElements after reverse: \n     ";
    std::copy (v.begin (), v.end (), Iter (std::cout, " "));

    std::cout << "\n\nA reverse_copy to cout: \n     ";
    std::reverse_copy (v.begin (), v.end (), 
                       Iter (std::cout, " "));
    std::cout << std::endl;

    return 0;
}


Program Output:

Elements before reverse: 
     1 2 3 4 5 6 7 8 9 10 

Elements after reverse: 
     10 9 8 7 6 5 4 3 2 1 

A reverse_copy to cout: 
     1 2 3 4 5 6 7 8 9 10

if u need more explaination plz PM me..;)