Problem 185. Data decompression

Created by Tomasz

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A chunk of data is to be 'decompressed'.Input:<ul><li>compressed: a row vector of uint8 values. This is the compressed data.</li><li>table: a cell-array of strings. Each string contains only '1's and '0's and represents a binary code.</li><li>alphabet: a string containing all possible symbols that may occur in the decompressed data. The symbol at alphabet(x) is encoded with the code at table{x}.</li></ul>Output:<ul><li>decompressed: a string with the decoded message.</li></ul>Example:<pre class="language-matlab">compressed=[93,85,127]
table={'1','010'}
alphabet='al'
==> decompressed = 'laaalalalaaaaaaa'
</pre>because:<pre class="language-matlab">[93,85,127] = '01011101 01010101 01111111' in binary
decoded from left to right:
'010 1 1 1 010 1 010 1 010 1 1 1 1 1 1 1'
= l a a a l a l a l a a a a a a a
</pre>Remarks: The message is such that always exactly all bits of <tt>compressed</tt> are used. The solution is unique (see <a href="http://en.wikipedia.org/wiki/Prefix_code">prefix-free code</a>).

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Last Solution submitted on May 26, 2021

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Tomasz on 1 Feb 2012

Update: two randomized tests added to the suite.

Nikolaos Nikolaou on 28 Oct 2020

i donnot understand the uint8 twist :/

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Problem 185. Data decompression

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