Find words that can be formed by characters

class Solution:
    def check(self, word, count):
        for i in range(len(word)):
            if count[ord(word[i]) - ord('a')] > 0:
                count[ord(word[i]) - ord('a')] -= 1
            else:
                return False
        return True
    def countCharacters(self, words: List[str], chars: str) -> int:
        count = [0] * 26
        for i in range(len(chars)):
            count[ord(chars[i]) - ord('a')] += 1
        res = 0
        for i in range(len(words)):
            copy = count.copy()
            if self.check(words[i], copy):
                res += len(words[i])

        return res

Find Words That Can Be Formed by Characters

Difficulty: Easy

You are given an array of strings words and a string chars.

A string is good if it can be formed by characters from chars (each character can only be used once).

Return the sum of lengths of all good strings in words.

 

Example 1:

Input: words = ["cat","bt","hat","tree"], chars = "atach"
Output: 6
Explanation: The strings that can be formed are "cat" and "hat" so the answer is 3 + 3 = 6.

Example 2:

Input: words = ["hello","world","leetcode"], chars = "welldonehoneyr"
Output: 10
Explanation: The strings that can be formed are "hello" and "world" so the answer is 5 + 5 = 10.

 

Constraints:

  • 1 <= words.length <= 1000
  • 1 <= words[i].length, chars.length <= 100
  • words[i] and chars consist of lowercase English letters.