#define U(a) ((unsigned char)(a)) #define twiddle(n) (( \ (U(n)<=9)? ((n)+161): \ (U(n)<=32? ((n)+163): \ (U(n) == 127? 196: (n))))) #define untwiddle(n) (( \ ((U(n)>=161 && (U(n))<=170)? ((n)-161): \ ((U(n)>=173 && (U(n))<=195)? ((n)-163): \ (U(n) == 196? 127: (n))))))