year28-fast.hrm

-- HUMAN RESOURCE MACHINE PROGRAM --

-- 28: Three Sort

-- INSTRUCTIONS: "For each THREE THINGS in the INBOX, send them to the
-- OUTBOX in order from smallest to largest."

-- AVAILABLE COMMANDS: INBOX, OUTBOX, COPYFROM, COPYTO, ADD, SUB,
-- BUMPUP, BUMPDN, JUMP, JUMPZ, JUMPN, COMMENT

-- SIZE: 58 commands (challenge 34)
-- AVERAGE RUNTIME: 78 steps (challenge 78)


-- Tile 0: First item in each set of three
-- Tile 1: Second item in each set of three
-- Tile 2: Third item in each set of three


-- Place the items on the floor immediately, compare them to each other
-- to determine total ordering, and pick them up in order to place in
-- the outbox.

a:
b:
c:
d:
e:
f:
-- Copy the three items to tiles 0, 1, and 2 in the order they come out
-- of the inbox.
    INBOX
    COPYTO   0
    INBOX
    COPYTO   1
    INBOX
    COPYTO   2
    SUB      1
    JUMPN    i
    COPYFROM 1
    SUB      0
    JUMPN    g
-- 0 <= 1 <= 2
    COPYFROM 0
    OUTBOX
    COPYFROM 1
    OUTBOX
    COPYFROM 2
    OUTBOX
    JUMP     f
g:
-- 1 is smallest
    COPYFROM 1
    OUTBOX
    COPYFROM 0
    SUB      2
    JUMPN    h
-- 1 < 2 <= 0
    COPYFROM 2
    OUTBOX
    COPYFROM 0
    OUTBOX
    JUMP     e
h:
-- 1 < 0 <= 2
    COPYFROM 0
    OUTBOX
    COPYFROM 2
    OUTBOX
    JUMP     d
i:
    COPYFROM 0
    SUB      2
    JUMPN    k
-- 2 is smallest
    COPYFROM 2
    OUTBOX
    COPYFROM 1
    SUB      0
    JUMPN    j
-- 2 <= 0 <= 1
    COPYFROM 0
    OUTBOX
    COPYFROM 1
    OUTBOX
    JUMP     c
j:
-- 2 <= 1 <= 0
    COPYFROM 1
    OUTBOX
    COPYFROM 0
    OUTBOX
    JUMP     b
k:
-- 0 <= 2 <= 1
    COPYFROM 0
    OUTBOX
    COPYFROM 2
    OUTBOX
    COPYFROM 1
    OUTBOX
    JUMP     a


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