PROC Triangle(BYTE level)
  INT v,i
  BYTE x,y
  BYTE ARRAY widths(20)
  CHAR ARRAY tmp(5)

  v=1
  FOR y=1 TO level-1
  DO
    v==+y
  OD
  FOR x=0 TO level-1
  DO
    StrI(v+x,tmp)
    widths(x)=tmp(0)
  OD

  v=1
  FOR y=1 TO level
  DO
    FOR x=0 TO y-1
    DO
      StrI(v,tmp)
      FOR i=tmp(0) TO widths(x)-1
      DO
        Put(32)
      OD
      Print(tmp)
      IF x<y-1 THEN
        Put(32)
      ELSE
        PutE()
      FI
      v==+1
    OD
  OD
RETURN

PROC Main()
  BYTE LMARGIN=$52,oldLMARGIN

  oldLMARGIN=LMARGIN
  LMARGIN=0 ;remove left margin on the screen

  Put(125) PutE() ;clear the screen
  Triangle(5)
  PutE()
  Triangle(13)

  LMARGIN=oldLMARGIN ;restore left margin on the screen
RETURN