w$="Hello World! "!1 BUTTON 0 TEXT w$ AT 0,0!PAUSE .1!IF BUTTON_PRESSED("0") THEN f=1-f!k=LEN(w$)-1!IF f THEN w$=RIGHT$(w$,1)&LEFT$(w$,k) ELSE w$=RIGHT$(w$,k)&LEFT$(w$,1)!GOTO 1