class Solution { public int solution(int order) { int answer = 0; String str = String.valueOf(order); for(int i = 0; i < str.length(); i++) { if(str.charAt(i) == '3' || str.charAt(i) == '6' || str.charAt(i) == '9' ) { answer++; } } return answer; } }

class Solution { public int solution(String number) { int answer = 0; for(int i = 0; i < number.length(); i++) { answer += Integer.parseInt(number.substring(i, i+1)); } answer %= 9; return answer; } }

class Solution { public int solution(int n) { int answer = 0; if(n % 6 == 0) { answer = n / 6; } else { for(int i = 1; ;i++) { if( i % n == 0 && i % 6 == 0) { answer = i / 6; break; } } } return answer; } }

class Solution { public int solution(int num, int k) { int answer = -1; String str = String.valueOf(num); for(int i = 0; i < str.length(); i++) { String numCheck = str.substring(i, i+1); if(Integer.parseInt(numCheck) == k) { answer = i + 1; break; } } return answer; } }

class Solution { public int solution(int a, int b, int c) { int answer = 0; int[] numbers = {a, b, c}; int count = 0; for(int i = 0; i < numbers.length; i++) { for(int j = i+1; j < numbers.length; j++) { if(numbers[i] == numbers[j]) { count++; } } } int num1 = 0, num2 = 0, num3 = 0; if(count == 0) { answer = a + b + c; } else if (count == 3) { for(int i = 0; i < numbers.length; i++) { num1 += (i..