Exercise 3-3

# Include <stdio. h>
# Include <stdlib. h>

/*
Compile the function char * expand (const char * ss, char * DS) to write stenographer symbols similar to a-Z in the string SS in the string DS
Expands to an equivalent complete list abcdef... Z. This function can process uppercase and lowercase letters and numbers, and can process
A-B-c, a-z0-9 And-a-Z and other similar situations. As the leading and trailing-character is outprinted.
Several examples are provided:
A-F> abcdef
F-A> fedcba
A-F-A> abcdefedcba
A-A> A-
A-9-0> a-9876543210
A -- B> A -- B
-A-c>-ABC
A-A> A-
> The character on the right is the converted character.
*/
Char * expand (const char * ss, char * DS)
{
Char * ds_head = Ds;
Const char * ITER, * iter_l;
Char temp;

If (Ss = NULL) return NULL;
If (DS = NULL) return NULL;/***** Exception !!! *******/
If (Ss = DS) return NULL;/* error, SS cannot be modified through ds to protect the original SS */
/*************************************** *******************/
If (* Ss = '-') * DS ++ = * ss ++;/* when the first position of the string is */
For (; * ss! = '/0'; SS ++)
{
If (* Ss = '-'){
Iter = ss-1; iter_l = SS + 1;

If (* iter_l> = '0' & * iter_l <= '9 '&&
* ITER> = '0' & * ITER <= '9 '&&
* Iter! = * Iter_l)
{/*-Number ***************
*********************/
If (* ITER <* iter_l) {/* ascending order 0-9 */
-- Ds;
For (temp = * ITER; temp <* iter_l; temp ++ ){
* (DS ++) = temp;
}
Continue;
}
/* 9-0 in descending order */
-- Ds;
For (temp = * ITER; temp> * iter_l; temp --){
* (DS ++) = temp;
}
Continue;
}/* End with a number *************
**********************/
Else if (* iter_l> = 'A' & * iter_l <= 'Z '&&
* ITER> = 'A' & * ITER <= 'Z '&&
* Iter! = * Iter_l)
{/*-Lowercase letter **********
********************/
If (* ITER <* iter_l) {/* ascending a-z */
-- Ds;
For (temp = * ITER; temp <* iter_l; temp ++ ){
* (DS ++) = temp;
}
Continue;
}
/* Descending Z-*/
-- Ds;
For (temp = * ITER; temp> * iter_l; temp --){
* (DS ++) = temp;
}
Continue;
}/****** Lowercase letter ending ****
**********************/

Else if (* iter_l> = 'A' & * iter_l <= 'Z '&&
* ITER> = 'A' & * ITER <= 'Z '&&
* Iter! = * Iter_l)
{/*-UPPERCASE letters **********
********************/
If (* ITER <* iter_l) {/* ascending A-Z */
-- Ds;
For (temp = * ITER; temp <* iter_l; temp ++ ){
* (DS ++) = temp;
}
Continue;
}
/* Z-A in descending order */
-- Ds;
For (temp = * ITER; temp> * iter_l; temp --){
* (DS ++) = temp;
}
Continue;
}/***** End with uppercase letters *****
*********************/

If neither else {/* is available, copy -*/
* (DS ++) = '-';
}

}/* If ends */
Else {/* Copy as is */
* (DS ++) = * ss;
}
}/* For end */

/* Add '/0' to the last position of DS '*/
* DS = '/0 ';

Return ds_head;
}
/*
Although a program in this function can be written in inline mode, it is not written because of the waste of parameter passing. Therefore, it is a bit redundant.
*/
Int main (void)
{
Char A [100000] = "-------- a-zz-aA-ZZ-A0-99-09-aa-b -------- ";
Char B [100000];
Char * C;
Printf ("1: % s/n", );
C = expand (A, B );
Printf ("2: % s/n", C );
Printf ("3: % s/n", expand (a, B ));
 
System ("pause ");

Return 0;
}