Consider the following C program:

#include

void fun1 (char *s1, char *s2) {

          char *tmp ;

          tmp = s1 ;

          s1 = s2 ;

          s2 = tmp ;

}

void fun2 (char **s1, char **s2) {

          char *tmp ;

          tmp = * s1 ;

          * s1 = * s2 ;

          * s2 = tmp ;

}

int main ( ) {

          char *str1 = “Hi”, *str2 = “Bye” ;

          fun1 (str1, str2) ;            printf (“%s  %s  “,    str1,  str2) ;

          fun2 (&str1, &str2) ;      printf (“%s %s “,   str1, str2) ;

          return 0 ;

}

The output of the program above is