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// This file is part of www.nand2tetris.org
// and the book "The Elements of Computing Systems"
// by Nisan and Schocken, MIT Press.
// File name: projects/08/ProgramFlow/FibonacciSeries/FibonacciSeries.vm
// Puts the first argument[0] elements of the Fibonacci series
// in the memory, starting in the address given in argument[1].
// Argument[0] and argument[1] are initialized by the test script
// before this code starts running.
push argument 1
pop pointer 1 // that = argument[1]
push constant 0
pop that 0 // first element in the series = 0
push constant 1
pop that 1 // second element in the series = 1
push argument 0
push constant 2
sub
pop argument 0 // num_of_elements -= 2 (first 2 elements are set)
label MAIN_LOOP_START
push argument 0
if-goto COMPUTE_ELEMENT // if num_of_elements > 0, goto COMPUTE_ELEMENT
goto END_PROGRAM // otherwise, goto END_PROGRAM
label COMPUTE_ELEMENT
push that 0
push that 1
add
pop that 2 // that[2] = that[0] + that[1]
push pointer 1
push constant 1
add
pop pointer 1 // that += 1
push argument 0
push constant 1
sub
pop argument 0 // num_of_elements--
goto MAIN_LOOP_START
label END_PROGRAM
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