#include #include #include #include #define ISLOWER(c) ('a' <= (c) && (c) <= 'z') #define TOUPPER(c) (ISLOWER(c) ? 'A' + ((c) - 'a') : (c)) #define XOR(e, f) (((e) && !(f)) || (!(e) && (f))) int main() { int i; for (i = 0; i < 256; i++) { if (XOR(islower(i), ISLOWER(i)) || toupper(i) != TOUPPER(i)) return 2; } return 0; }