程序代码：

#include<stdio.h>
#include<string.h>
int main ( void )
{
   char *r1 = "hello" ;
   char r2[] = "hello" ;
   char r3[] = {'h','e','l','l','o'} ;

   printf("r3[5] : %c\n", *(r3+5) ) ;
   printf("r3[6] : %c\n", *(r3+6) ) ;
   printf("r1 : %d %d \n", sizeof( r1 ) , strlen( r1 ) ) ;
   printf("r2 : %d %d \n", sizeof( r2 ) , strlen( r2 ) ) ;
   printf("r3 : %d %d \n", sizeof( r3 ) , strlen( r3 ) ) ;

   return 0 ;
}