48. Centred text
    ~~~~~~~~~~~~
This is a Procedure for automatically centering a short piece of text on a
line, without having to figure out what value TAB to use. You call it with
PROCcentre(40,"HELLO THERE") or PROCcentre(80,A$) and so on, where the figure
is the width of the screen in the current Mode; 20, 40 or 80.

 100 DEFPROCcentre(width%,text$)
 110 PRINTTAB((width%-LEN(text$))DIV2)text$
 120 ENDPROC