LeetCode 737, Medium. Topics: Array, Hash Table, String, Depth-First Search, Breadth-First Search, Union Find. View on LeetCode.
Generate this problem as a practice environment: tested reference solution, 13 parametrized pytest cases, and a playground notebook:
Problem
We can represent a sentence as an array of words, for example, the sentence "I am happy with leetcode" can be represented as arr = ["I","am","happy","with","leetcode"].
Given two sentences sentence1 and sentence2 each represented as a string array, and given an array of string pairs similarPairs where similarPairs[i] = [xi, yi] indicates that the two words xi and yi are similar.
Return true if sentence1 and sentence2 are similar, or false if they are not similar.
Two sentences are similar if:
- They have the same length (i.e., the same number of words)
sentence1[i] and sentence2[i] are similar.
Notice that a word is always similar to itself, also notice that the similarity relation is transitive. For example, if the words a and b are similar, and the words b and c are similar, then a and c are similar.
Examples
Constraints
- 1 <= sentence1.length, sentence2.length <= 1000
- 1 <= sentence1[i].length, sentence2[i].length <= 20
- sentence1[i] and sentence2[i] consist of lower-case and upper-case English letters.
- 0 <= similarPairs.length <= 2000
- similarPairs[i].length == 2
- 1 <= xi.length, yi.length <= 20
- xi and yi consist of English letters.
Solution
Reference implementation from solution.py on GitHub, full suite in test_solution.py:
Complexity
NeetCode All. Last modified on September 7, 2026