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copied!<p>In Python3</p> <pre><code>>>> from collections import Counter >>> count_hash=Counter() >>> T=(3, 5, 1, 3, 5, 48, 4, 7, 13, 55, 65, 4, 7, 13, 32) >>> for i in range(2,len(T)+1): ... for j in range(len(T)+1-i): ... count_hash[T[j:j+i]]+=1 ... >>> for k,v in count_hash.items(): ... if v >= 2: ... print(k,v) ... (3, 5) 2 (4, 7, 13) 2 (7, 13) 2 (4, 7) 2 </code></pre> <p>Do you need to filter the (7,13) and the (4,7) out? What happens if there was also (99, 7, 14) in the sequence?</p> <p>a <code>Counter</code> is just like a hash used to keep track of the number of times we see each substring<br> The two nested for loops produce all the substrings of <code>T</code>, using <code>count_hash</code> to accumulate the count of each substring.<br> The final for loop filters all those substrings that only occurred once</p> <p>Here is a version with a filter</p> <pre><code>from collections import Counter def substrings(t, minlen=2): tlen = len(t) return (t[j:j+i] for i in range(minlen, tlen+1) for j in range(tlen+1-i)) def get_freq(*t): counter = Counter(substrings(t)) for k in sorted(counter, key=len): v=counter[k] if v < 2: del counter[k] continue for t in substrings(k): if t in counter: if t==k: continue counter[k]+=counter[t]-v del counter[t] return counter print(get_freq(3, 5, 1, 3, 5, 48, 4, 7, 13, 55, 65, 4, 7, 13, 32, 4, 7)) print(get_freq(1,2,3,4,1,2,3,4,1,2,7,8,7,8,3,4,3,4,1,2)) </code></pre> <p>the output is</p> <pre><code>Counter({(4, 7, 13): 3, (3, 5): 2}) Counter({(1, 2, 3, 4, 1, 2): 8, (7, 8): 2}) # Is this the right answer? </code></pre> <p>Which is why I asked how the filtering should work for the sequence I gave in the comments</p>

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