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POFind 'connected components' in graph
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  1. POFind 'connected components' in graph
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    copied!<p>I'm building a thesaurus using a <code>HashMap &lt;String,ArrayList&lt;String&gt;&gt;</code> to hold words and their synonyms (this data structure is required).</p> <p>For the purpose of the assignment, the synonymity relation is considered transitive. (We can imagine the thesaurus as a graph). What I'm trying to accomplish is to print this graph in a text file, with a connected component on each line. In other words, all the words that can be pooled together as synonyms should go on a single line.</p> <pre><code>public void save() { try { FileWriter fw = new FileWriter(defaultDefinitionFile); BufferedWriter out = new BufferedWriter(fw); Set&lt;String&gt; keys = thesaurus.keySet(); Iterator&lt;String&gt; ite = keys.iterator(); while (ite.hasNext()) { String key = ite.next(); out.write(key); ArrayList&lt;String&gt; synonyms = thesaurus.get(key); Iterator&lt;String&gt; i = synonyms.iterator(); while (i.hasNext()) { String syn = i.next(); out.write(","+syn); keys.remove(syn); } out.write("\r\n"); } out.close(); fw.close(); } catch (Exception e) { System.out.println("Error writing to file"); e.printStackTrace(); } } </code></pre> <p>This is how I pictured it to happen:</p> <p>Print a word along with each of its synonyms, then remove those synonyms from the data structure so we don't have duplicate lines.</p> <p>Problem is of course that I can't delete anything while i'm iterating over the content of the hashmap.</p> <p>Any alternative approaches I'm missing?</p> <p>P.S. I'm keeping the 'graph' metaphor throughout only because i needed the title to be eloquent and succint. I understand that this metaphor is limited in usefulness.</p>
 

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