Conjecture

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//package kisa41;

import java.util.Scanner;

public class Kisa41 {

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        Scanner s = new Scanner(System.in);
        
        long a = s.nextLong();
        
        if(a<6){
            a = 6;
        }
        
        while(true){
            a++;
            if(!(a%3 == 0)){
                System.out.println(a);
                break;
            }
        }
    }
    
}

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: ACCEPTED

Test 5

Verdict: ACCEPTED

Test 6

Verdict: ACCEPTED

Test 7

Verdict: ACCEPTED

Test 8

Verdict: ACCEPTED

Test 9

Verdict: ACCEPTED

Test 10

Verdict: ACCEPTED

Test 11

Verdict: ACCEPTED

Test 12

Verdict: ACCEPTED

Test 13

Verdict: ACCEPTED

Test 14

Verdict: ACCEPTED

Test 15

Verdict: ACCEPTED

Test 16

Verdict: ACCEPTED