Method of implementing string inversion function char *reverse (char *str) using recursive and non-recursive C language _c language

The code looks like this:

Copy Code code as follows:

//recursive implementation string inversion
Char *reverse (char *str)
{
if (!STR)
{
return NULL;
}

int len = strlen (str);
if (Len > 1)
{
Char Ctemp =str[0];
Str[0] = str[len-1];
Str[len-1] = '/0 ';//The last character will not be processed the next time it is recursive
Reverse (str+1); Recursive call
Str[len-1] = ctemp;
}

return str;
}

//non-recursive implementation of string inversion
Char *reverse (char *str)
{
if (!STR)
{
return NULL;
}

int len = strlen (str);
char temp;
for (int i = 0; i < LEN/2; i++)
{
Exchange two characters before and after the corresponding positions
temp = * (str + i);
* (str + i) = * (str + len-1-i);
* (str + len-1-i) = temp;
}

return str;
}
int _tmain (int argc, _tchar* argv[])
{
Char src[] = {"ABCdef"};
Char *pdest = reverse (src);
GetChar ();
return 0;
}