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$ curl repovive.com/roadmaps/python/tuples-sets/common-characters-implementation

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$ curl repovive.com/roadmaps/python/tuples-sets/common-characters-implementation

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Common Characters - Implementation - Tuples & Sets | Python | Repovive

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Python9 sections · 462 units23h total

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Common Characters - Implementation

The code

Here's the solution:

def count_common_chars(word1, word2):
    chars1 = set(word1)
    chars2 = set(word2)
    common = chars1 & chars2
    return len(common)

Or as a one-liner:

def count_common_chars(word1, word2):
    return len(set(word1) & set(word2))

Time: $O(n + m)$ where $n$ and $m$ are the string lengths. Space: $O(\min(n, m))$ for the smaller character set.