884. Uncommon Words from Two Sentences

Problem Link

Description

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A sentence is a string of single-space separated words where each word consists only of lowercase letters.

A word is uncommon if it appears exactly once in one of the sentences, and does not appear in the other sentence.

Given two sentences s1 and s2, return a list of all the uncommon words. You may return the answer in any order.

 

Example 1:

Input: s1 = "this apple is sweet", s2 = "this apple is sour"

Output: ["sweet","sour"]

Explanation:

The word "sweet" appears only in s1, while the word "sour" appears only in s2.

Example 2:

Input: s1 = "apple apple", s2 = "banana"

Output: ["banana"]

 

Constraints:

• 1 <= s1.length, s2.length <= 200
• s1 and s2 consist of lowercase English letters and spaces.
• s1 and s2 do not have leading or trailing spaces.
• All the words in s1 and s2 are separated by a single space.

Solution

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Python3

class Solution:
    def uncommonFromSentences(self, s1: str, s2: str) -> List[str]:
        u1 = Counter(s1.split())
        u2 = Counter(s2.split())
        res = []
 
        for x in u1:
            if u1[x] == 1 and u2[x] == 0:
                res.append(x)
        
        for x in u2:
            if u2[x] == 1 and u1[x] == 0:
                res.append(x)
 
        return res