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POCounting clusters in a hash set
 

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    <p>I'm trying to debug a hashset implementation (for a school assignment). Collisions are being managed via linear probing, and I need to count the number of clusters of a given size for the debug routine. I worked this up:</p> <pre><code>// really just hoping that a 50+ cluster doesn't occur int clusters[50]; int count = 0; for (int i=0; i &lt; hashset-&gt;dim; i++) { if (hashset-&gt;array[i] != NULL) { count++; } else { if (count == 0) continue; if (clusters[count] == NULL) clusters[count] = 0; clusters[count]++; count = 0; } } for (int i=1; i &lt; 50; i++) { if (clusters[i] != NULL &amp;&amp; clusters[i] != 0) printf("%d clusters of size %d\n", clusters[i], i); } </code></pre> <p>Seems to make sense, but when I run it I get...</p> <pre><code>25143 entries in hashset 50286 dimension of the hash array 4585 clusters of size 1 2134 clusters of size 2 1102 clusters of size 3 696 clusters of size 4 388 clusters of size 5 264 clusters of size 6 173 clusters of size 7 104 clusters of size 8 89 clusters of size 9 51 clusters of size 10 46 clusters of size 11 35 clusters of size 12 26 clusters of size 13 22 clusters of size 14 17 clusters of size 15 134553327 clusters of size 16 134634407 clusters of size 17 112 clusters of size 18 6 clusters of size 19 134553324 clusters of size 20 134634399 clusters of size 21 107 clusters of size 22 3 clusters of size 23 2 clusters of size 24 134634401 clusters of size 25 107 clusters of size 26 134107784 clusters of size 27 134556210 clusters of size 28 [... more nonsense] </code></pre> <p>So initially it seems to give sane output.. lots of clusters, but whatever. My thinking is that the way-too-huge numbers should actually be 0 - they're clusters which don't actually exist but for some reason are still getting printed. I just have no idea why...</p>
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