Description
https://leetcode.com/problems/uncommon-words-from-two-sentences/
We are given two sentences A and B. (A sentence is a string of space separated words. 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.
Return a list of all uncommon words.
You may return the list in any order.
Example 1:
Input: A = "this apple is sweet", B = "this apple is sour" Output: ["sweet","sour"]
Example 2:
Input: A = "apple apple", B = "banana" Output: ["banana"]
Note:
0 <= A.length <= 2000 <= B.length <= 200AandBboth contain only spaces and lowercase letters.
Explanation
Count A words and B words separately and find out those words only occur either in A or B once.
Python Solution
class Solution:
def uncommonFromSentences(self, A: str, B: str) -> List[str]:
results = []
a_counter = {}
a_words = A.split()
for word in a_words:
a_counter[word] = a_counter.get(word, 0) + 1
b_counter = {}
b_words = B.split()
for word in b_words:
b_counter[word] = b_counter.get(word, 0) + 1
for key, value in a_counter.items():
if key not in b_counter and value == 1:
results.append(key)
for key, value in b_counter.items():
if key not in a_counter and value == 1:
results.append(key)
return results- Time Complexity: O(N).
- Space Complexity: O(N).