qr code

class Solution {
    public String solution(int q, int r, String code) {
       StringBuffer answer = new StringBuffer();
        
        for(int i=0; i<code.length(); i++){
            if(i % q == r ){
                answer.append(code.charAt(i));
            }
            
        }
        return answer.toString();
    }
}

 

class Solution {
    public String solution(int q, int r, String code) {
        String answer = "";

        for(int i = 0; i < code.length(); i ++){

            if(i % q == r){
                answer += code.charAt(i);
            }
        }

        return answer;
    }
}

 

class Solution {
    public String solution(int q, int r, String code) {
            String answer = "";
        String[] arr = code.split("");
        for (int i = 0; i < arr.length; i++) {
            if (i % q == r) {
                answer += arr[i];
            }
        }
        return answer;
    }
}