정수 이어붙여서 비교하기

class Solution {
    public int solution(int a, int b) {
        int answer = 0;
        int aLong = Integer.parseInt(""+a+b);
        int bLong = Integer.parseInt(""+b+a);
        answer = aLong > bLong ? aLong : bLong;

        return answer;
    }
}

문자열에 int를 이어붙이면,
 문자열이 리턴되는 속성을 이용한 방법입니다
 출처: https://hianna.tistory.com/524 [어제 오늘 내일:티스토리] 

class Solution {
    public int solution(int a, int b) {
        String strA = String.valueOf(a);
        String strB = String.valueOf(b);
        String strSum1 = strA + strB;
        String strSum2 = strB + strA;
        return Math.max(Integer.valueOf(strSum1), Integer.valueOf(strSum2));
    }
}

math.max 메소드 사용한 거 

class Solution {
    public int solution(int a, int b) {
        return Math.max(Integer.parseInt(a + "" + b), Integer.parseInt(b + "" + a));
    }
}