Where am I wrong?
package com.codegym.task.task07.task0713;
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.List;
/*
Playing Javarella
*/
public class Solution {
public static void main(String[] args) throws Exception {
BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
ArrayList<Integer> mainArrList = new ArrayList<>();
ArrayList<Integer> divByTwo = new ArrayList<>();
ArrayList<Integer> divByThree = new ArrayList<>();
ArrayList<Integer> extra = new ArrayList<>();
for (int i = 0; i < 20; i++) {
int num = Integer.parseInt(reader.readLine());
mainArrList.add(num);
}
for (int num : mainArrList) {
if (num % 3 == 0) {
divByThree.add(num);
}
}
for (int num : mainArrList) {
if(num%2 ==0)
divByTwo.add(num);
}
for (int num : mainArrList) {
if(num % 3 != 0 &&num % 2 != 0)
extra.add(num);
}
// printList(mainArrList);
//System.out.println();////System.out.println();
printList(divByThree);
//System.out.println();
printList(divByTwo);
//System.out.println();
printList(extra);
}
public static void printList(List<Integer> list) {
// write your code here
for (int number : list) {
System.out.println(number);
}
}
}