[알고리즘문제풀기] 369게임

문제

내가 작성한 정답

class Solution {
    public int solution(int order) {
        int answer = 0;
        char[] clap = String.valueOf(order).toCharArray();
        for(char c: clap){
            if(c=='3'|| c=='6'||c=='9') answer++;
        }
        return answer;
    }
}

class Solution {
    public int solution(int order) {
        int answer = 0;
        char[] clap = String.valueOf(order).toCharArray();
        for(char c: clap){
            if((c-'0')%3==0 && c!='0') answer++;
        }
        return answer;
    }
}

class Solution {
    public int solution(int order) {
        return (int) String.valueOf(order).chars()
                .map(c->c-'0')
                .filter(i->i%3==0 && i!=0)
                .count();   //count는 long을 리턴한다
    }
}

다른 사람들의 정답

class Solution {
    public int solution(int order) {
        int answer = 0;

        String str = order+"";

        for(int i=0; i<str.length(); i++){
            char c = str.charAt(i);
            if(c=='3'||c=='6'||c=='9') answer++;
        }

        return answer;
    }
}