Reply To: Reverse a string without using library function

[Humayan]

Here’s one without a loop:

C++

/**************************************************************** * File Name : c:programshelpshell.cpp * Date : December,19,2007 * Comments : new project * Compiler/Assembler : * Program Shell Generated At: 2:21:22 p.m. =-=-=-=-=-=-=-=--=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=*/ #include < iostream > //#include < string.h > //#include < conio.h > //#include < math.h > //#include < iomanip > //#include < ctype.h > using namespace std; //@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ FUNCTION PROTOTYPES @@@@@@@@@@@@@@@@@@@@@@@@@@ void reverseString ( char * string , int & front , int & rear ); void reverseStringDriver ( char * string , int length ); //################################################################################## //main function ****************************** int main ( ) { char string [ 10 ] ; strcpy ( string , "hellos" ); reverseStringDriver ( string , 6 ); cout << "reversed string : " << string << endl ; return 0 ; } /******************************* FUNCTION DEFINITION ****************************** Name : reverseString Parameters : string a(n) char * ( char * ) , front a(n) int ( int ) , rear a(n) int ( int ) Returns: Void type Comments: ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/ void reverseString ( char * string , int & front , int & rear ) { if ( front > rear ) return; char temp; temp = string [ front ]; string [ front ] = string [ rear ]; string [ rear ] = temp; front ++; rear --; return; } /******************************* FUNCTION DEFINITION ****************************** Name : reverseStringDriver Parameters : string a(n) char * Returns: Void type Comments: ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/ void reverseStringDriver ( char * string , int length ) { int front = 0 , rear = length - 1; reverseString ( string , front , rear ); return; }

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/**************************************************************** * File Name : c:programshelpshell.cpp * Date : December,19,2007 * Comments : new project * Compiler/Assembler : * Program Shell Generated At: 2:21:22 p.m. =-=-=-=-=-=-=-=--=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=*/   #include < iostream > //#include < string.h > //#include < conio.h > //#include < math.h > //#include < iomanip > //#include < ctype.h > using namespace std;   //@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ FUNCTION PROTOTYPES @@@@@@@@@@@@@@@@@@@@@@@@@@ void reverseString ( char * string , int & front , int & rear ); void reverseStringDriver ( char * string , int length ); //##################################################################################   //main function ****************************** int main ( ) { char string [ 10 ] ; strcpy ( string , "hellos" ); reverseStringDriver ( string , 6 ); cout << "reversed string : " << string << endl ; return 0 ; } /******************************* FUNCTION DEFINITION ****************************** Name : reverseString Parameters : string a(n) char * ( char * ) , front a(n) int ( int ) , rear a(n) int ( int ) Returns: Void type Comments: ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/ void reverseString ( char * string , int & front , int & rear ) {   if ( front > rear ) return; char temp;   temp = string [ front ]; string [ front ] = string [ rear ]; string [ rear ] = temp;   front ++; rear --; return; } /******************************* FUNCTION DEFINITION ****************************** Name : reverseStringDriver Parameters : string a(n) char *   Returns: Void type Comments:   ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/ void reverseStringDriver ( char * string , int length ) { int front = 0 , rear = length - 1; reverseString ( string , front , rear ); return; }