1#include <stdlib.h> 2#include <ctype.h> 3 4int main () 5{ 6 char* buf = "hello"; 7 return ! ((toupper (buf[0]) == 'H' && toupper ('z') == 'Z' && 8 tolower (buf[4]) == 'o' && tolower ('X') == 'x' && 9 isdigit (buf[3])) == 0 && isalnum ('4')); 10} 11