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 | NUM_SQUARE_ROOTS EQU 255
GetSquareRoot:
; Return the square root of de in b.
; Rather than calculating the result, we take the index of the
; first value in a table of squares that isn't lower than de.
	ld hl, .Squares
	ld b, 0
.loop
; Make sure we don't go past the end of the table.
	inc b
	ld a, b
	cp NUM_SQUARE_ROOTS
	ret z
; Iterate over the table until b**2 >= de.
	ld a, [hli]
	sub e
	ld a, [hli]
	sbc d
	jr c, .loop
	ret
.Squares:
for x, 1, NUM_SQUARE_ROOTS + 1
	dw x**2
endr
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