#include <stdio.h>
 
int is_prefix(const char *target, const char *prefix);
 
int main(void)
{
   char a[] = "Mr. Smith";
 
   if (is_prefix(a, "Mr.") == 1)
      printf("%s --> Bay\n", a);
   else if (is_prefix(a, "Mrs.") == 1)
      printf("%s --> Bayan\n", a);
   else
      printf("%s --> unknown\n", a);
 
   return 0;
}
/***********************************/
int is_prefix(const char *target, const char *prefix)
{
   for (; *prefix == *target; prefix++, target++)
      if (*prefix == '\0')
         break;
   return *prefix == '\0';
}