스킬트리

class Solution {
    public int solution(String skill, String[] skill_trees) {
        
        int answer = 0;
        
        for(int i = 0; i < skill_trees.length; ++i)
        {
            String tree = skill_trees[i];
            StringBuilder sb = new StringBuilder();
            for(int j = 0; j < tree.length(); ++j)
            {
                Character cur = tree.charAt(j);
                if(skill.contains(cur.toString()))
                {
                    sb.append(cur);
                }
            }
            
            boolean success = true;
            for(int j = 0; j < sb.length(); ++j)
            {
                if(sb.charAt(j) != skill.charAt(j))
                {
                    success = false;
                    break;
                }
                    
            }
            if(success)
                answer++;
            
        }
        
        
        
        return answer;
    }
}