src/main/java/com/fishercoder/solutions/_1684.java

package com.fishercoder.solutions;

import java.util.HashSet;
import java.util.Set;

public class _1684 {
    public static class Solution1 {
        public int countConsistentStrings(String allowed, String[] words) {
            Set<Character> set = new HashSet<>();
            for (char c : allowed.toCharArray()) {
                set.add(c);
            }
            int count = 0;
            for (String word : words) {
                boolean isConsistent = true;
                for (char c : word.toCharArray()) {
                    if (!set.contains(c)) {
                        isConsistent = false;
                        break;
                    }
                }
                if (isConsistent) {
                    count++;
                }
            }
            return count;
        }
    }
}