mac上のgccで動きます

HelloWorld.c

#define _____________ main
#define ____________ int
#define ___________ char
#define __________ while
#define _________ printf
#define ________ "%s\n"
#define _______ 115
#define ______ _==108?__[4]=___:_==111?__[5]=___:_==114?__[6]=___

_____________(){ ____________ _;___________ __[7];___________ *___;
    __________(___++,_++<_______) 
    _==72?__[0]=___:_==87?__[1]=___:_==100?__[2]=___:_==101?__[3]=___:______:_;
    ___________ ____[11]={__[0],__[3],__[4],__[4],__[5],__[1],__[5],__[6],__[4],__[2]};
    _________(________,____);}

おもしろいw