C / C++ / MFC

#include <iostream><br />
#include <cstdio><br />
<br />
using namespace std;<br />
<br />
void reverseString(char *str, const int &len)<br />
{<br />
 for(int i=0; i<(len-1)-i; ++i)<br />
  str[i] ^= str[(len-1)-i] ^= str[i] ^= str[(len-1)-i];<br />
}<br />
<br />
int main()<br />
{<br />
 char str[] = "String to reverse!";<br />
 int len = strlen(str);<br />
<br />
 // in place reverse<br />
 cout << str << endl;<br />
 reverseString(str, len);<br />
 cout << str << endl;<br />
 return 0;<br />
}

void ReverseString( char* sz, size_t len )
{
   char ch;
 
   for ( size_t idx = 0; idx < len / 2; ++idx )
   {
      ch = sz[idx];
      sz[idx] = sz[len - idx - 1];
      sz[len - idx - 1] = ch;
   }
}

void Reverse(char *src)<br />
{<br />
	char *p = strchr(src, '\0') - 1;<br />
	<br />
	while (src < p)<br />
	{<br />
          *src ^= *p ^= *src ^= *p;<br />
	  src++;<br />
	  p--;<br />
	}<br />
}

1. Add a hidden button to your dialog, with id ID_RUN_LOOP.
   
2. Write a handler for the ID_RUN_LOOP command. The handler should execute the for loop.
   
3. In your dialog's OnInitDialog() handler, do this: PostMessage (WM_COMMAND, ID_RUN_LOOP);