Convert from binary to unary in 7x7 Manufactoria In the game manufactoria, take in a binary number and output that number of red pieces.
The catch? The board-size is only 7x7:

Here's the manufactoria code for the problem:

http://pleasingfungus.com/Manufactoria/?ctm=Razors;Treat_the_input_as_a_binary_number_and_output_that_number_of_reds;b:r|brr:rrrr|brb:rrrrr|brbb:rrrrrrrrrrr|:|brrrr:rrrrrrrrrrrrrrrr|brbr:rrrrrrrrrr;7;3;0;

I have a solution, so it most definitely exists.

EDIT: Least "total parts" wins (as reported by manufactoria engine)
21 20 19 parts! Ha!



http://pleasingfungus.com/Manufactoria/?lvl=32&amp;code=q12:9f0;c12:8f3;g9:8f1;q9:9f4;b10:8f3;p10:9f0;r10:10f1;y11:9f0;g12:5f3;c12:6f3;r9:6f3;c9:7f2;r10:6f0;p10:7f2;q11:7f1;i12:7f7;p13:7f6;r13:6f0;c13:8f0;&amp;ctm=Razors;Treat_the_input_as_a_binary_number_and_output_that_number_of_reds;b:r|brr:rrrr|brb:rrrrr|brbb:rrrrrrrrrrr|:|brrrr:rrrrrrrrrrrrrrrr|brbr:rrrrrrrrrr;7;3;0;

Edit 2: Back to the original design, but with two parts shaved off by creative reuse of conveyors.  The 7 &times; 7 board really does start to feel confining &mdash; I've come up with several ways to shrink this further, if I only had one more row of vertical space...