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copied!<p>If you want bits, then you have to do both packing and unpacking manually. Neither Ruby nor any other common-use language will do it for you.</p> <p>Your array contains strings that are groups of characters, but you need to build an array of bytes and write those bytes into the file.</p> <p>From this: <code>["010", "1111", "10", "10", "110", "1110", "001", "110", "000", "10", "011"]</code></p> <p>you should build these bytes: <code>01011111 01011011 10001110 00010011</code></p> <p>Since it's just four bytes, you can put them into a single 32-bit number <code>01011111010110111000111000010011</code> that is <code>5F5B8E13</code> hex.</p> <p>Both samples of your code do different things. The first one writes into the file a string representation of a Ruby array. The second one writes 32 bytes where each is either <code>48</code> ('0') or <code>49</code> ('1').</p> <p>If you want bits, then your output file size should be just four bytes.</p> <p>Read about bit operations to learn how to achieve that.</p> <hr> <p>Here is a draft. I didn't test it. Something may be wrong.</p> <pre><code>a = ["010", "1111", "10", "10", "110", "1110", "001", "110", "000", "10", "011"] # Join all the characters together. Add 7 zeros to the end. bit_sequence = a.join + "0" * 7 # "010111110101101110001110000100110000000" # Split into 8-digit chunks. chunks = bit_sequence.scan(/.{8}/) # ["01011111", "01011011", "10001110", "00010011"] # Convert every chunk into character with the corresponding code. bytes = chunks.map { |chunk| chunk.to_i(2).chr } # ["_", "[", "\x8E", "\x13"] File.open("my_huffman.bin", 'wb' ) do |output| bytes.each { |b| output.write b } end </code></pre> <p>Note: seven zeros are added to handle case when the total number of characters is not divisible by 8. Without those zeros, <code>bit_sequence.scan(/.{8}/)</code> will drop the remaining characters.</p>

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