LeetCode: Word Pattern Solution

Approach

One hash table to map pattern to word

One hash table to check if word is already mapped by a pattern

Implementation

1var wordPattern = function (pattern, s) {
2  pattern = pattern.split("")
3  s = s.split(" ")
4
5  if (pattern.length !== s.length) return false
6
7  const patternWordMap = new Map()
8  const wordMapped = new Set()
9
10  for (let i = 0; i < pattern.length; i++) {
11    if (!patternWordMap.has(pattern[i]) && !wordMapped.has(s[i])) {
12      patternWordMap.set(pattern[i], s[i])
13      wordMapped.add(s[i])
14      continue
15    }
16
17    if (patternWordMap.get(pattern[i]) !== s[i]) return false
18  }
19
20  return true
21}

References

Original problem

Similar problems

Isomorphic Strings

Word Pattern II