# Powers: B=2 C=4, D=8, E=16, F=32, G=64, H=128, I=256, J=512, K=1024
INCREASE B INCREASE B
REPEAT B TIMES ( INCREASE C INCREASE C )
REPEAT C TIMES ( INCREASE D INCREASE D )
REPEAT D TIMES ( INCREASE E INCREASE E )
REPEAT E TIMES ( INCREASE F INCREASE F )
REPEAT F TIMES ( INCREASE G INCREASE G )
REPEAT G TIMES ( INCREASE H INCREASE H )
REPEAT H TIMES ( INCREASE I INCREASE I )
REPEAT I TIMES ( INCREASE J INCREASE J )
REPEAT J TIMES ( INCREASE K INCREASE K )

# Setting A
REPEAT h TIMES ( INCREASE A )

# Gate C := 1
CLEAR C
INCREASE C

REPEAT A TIMES (

  # D := parity(X)
  CLEAR D
  REPEAT X TIMES (
    CLEAR E
    INCREASE E
    REPEAT D TIMES ( CLEAR E )
    CLEAR D
    REPEAT E TIMES ( INCREASE D )
  )

  # I := floor(X/2) using toggler G
  CLEAR I
  CLEAR G
  REPEAT X TIMES (
    CLEAR E
    INCREASE E
    REPEAT G TIMES ( CLEAR E )
    CLEAR G
    REPEAT E TIMES ( INCREASE G )
    CLEAR H
    INCREASE H
    REPEAT G TIMES ( CLEAR H )
    REPEAT H TIMES ( INCREASE I )
  )

  # L := 1 if I==0 else 0
  INCREASE L
  REPEAT I TIMES ( CLEAR L )

  # M := (X==1) = L AND D
  REPEAT L TIMES ( REPEAT D TIMES ( INCREASE M ) )

  # Gated print + latch: C := 1 - M
  REPEAT C TIMES (
    PRINT X
    CLEAR C
    INCREASE C
    REPEAT M TIMES ( CLEAR C )
  )

  # If still active, update X
  REPEAT C TIMES (
    # N := 1 - D
    INCREASE N
    REPEAT D TIMES ( CLEAR N )

    # K := 3*X + 1
    CLEAR K
    REPEAT X TIMES ( INCREASE K INCREASE K INCREASE K )
    INCREASE K

    # J := I
    CLEAR J
    REPEAT I TIMES ( INCREASE J )

    # X := if even then J else K
    CLEAR X
    REPEAT N TIMES ( REPEAT J TIMES ( INCREASE X ) )
    REPEAT D TIMES ( REPEAT K TIMES ( INCREASE X ) )
  )

  # reset temps used in this iteration
  CLEAR M
  CLEAR N
)