class Solution {
    // time O(n^2)
    // space O(n)
    public int countConsistentStrings(String allowed, String[] words) {
        HashSet<Character> hashSet = new HashSet<Character>();
        int count = 0;

        for (int i = 0; i < allowed.length(); i++) {
            hashSet.add(allowed.charAt(i));
        }

        outerloop:
        for (int i = 0; i < words.length; i++) {
            String word = words[i];
            
            for (int j = 0; j < word.length(); j++) {
                if (!hashSet.contains(word.charAt(j))) {
                    continue outerloop;
                }
            }

            count++;
        }

        return count;
    }
}