[알고리즘] 369게임 Java

 

List 2개를 비교해서 중복된 값 카운트

import java.util.Arrays;
import java.util.List;
import java.util.function.Predicate;

class Solution {
    public int solution(int order) {
        int answer = 0;
        List<String> list = Arrays.asList("3", "6", "9");
        return (int) Arrays.asList(String.valueOf(order).split("")).stream()
        .filter(s -> list.stream().anyMatch(Predicate.isEqual(s)))
        .count();
    }
}

 

import java.util.Arrays;

class Solution {
    public int solution(int order) {
        return (int) Arrays.stream(String.valueOf(order).split("")).map(Integer::parseInt).filter(i -> i == 3 || i == 6 || i == 9).count();
    }
}

 

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

        while (order >= 1) {
            if (order % 10 == 3 || order % 10 == 6 || order % 10 == 9) answer ++;
            order /= 10;
        }

        return answer;
    }
}