Is there a way to optimize my code more?

import java.util.*;
public class Main
{
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        
        int J = in.nextInt() + 1;
        int A = in.nextInt();
        
        ArrayList<Integer>size[] = new ArrayList[3];
        
        for (int i = 0; i < 3; i++) {
            size[i] = new ArrayList<>();
        }
        
        for (int i = 1; i < J; i++) {
            char x = in.next().charAt(0);
            if (x == 'S') {
                size[0].add(i);
            } else if (x == 'M') {
                size[1].add(i);
            } else {
                size[2].add(i);
            }
        }
        
        ArrayList<Integer>arr[] = new ArrayList[J];
        
        for (int i = 0; i < J; i++) {
            arr[i] = new ArrayList<>();
        }
        
        for (int i = 0; i < A; i++) {
            char x = in.next().charAt(0);
            int num = in.nextInt();
            
            if (num < J) {
               if (x == 'S') {
                    arr[num].add(0);
                } else if (x == 'M') {
                    arr[num].add(1);
                } else {
                    arr[num].add(2);
                } 
            }
        }
        
        int count = 0;
        for (int i = 0; i < 3; i++) {
            while (!size[i].isEmpty()) {
                if (!arr[size[i].get(0)].isEmpty()) {
                    Iterator<Integer> iterator = arr[size[i].get(0)].iterator();
                    while (iterator.hasNext()) {
                        int adj = iterator.next();
                        if (adj <= i) {
                            count++;
                            iterator.remove();
                            break;
                        }
                    }
                }
                size[i].remove(0);
            }
        }
        
        System.out.println(count);
        
    }
}

import java.util.*;
public class Main
{
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        
        int J = in.nextInt() + 1;
        int A = in.nextInt();
        
        ArrayList<Integer>size[] = new ArrayList[3];
        
        for (int i = 0; i < 3; i++) {
            size[i] = new ArrayList<>();
        }
        
        for (int i = 1; i < J; i++) {
            char x = in.next().charAt(0);
            if (x == 'S') {
                size[0].add(i);
            } else if (x == 'M') {
                size[1].add(i);
            } else {
                size[2].add(i);
            }
        }
        
        ArrayList<Integer>arr[] = new ArrayList[J];
        
        for (int i = 0; i < J; i++) {
            arr[i] = new ArrayList<>();
        }
        
        for (int i = 0; i < A; i++) {
            char x = in.next().charAt(0);
            int num = in.nextInt();
            
            if (num < J) {
               if (x == 'S') {
                    arr[num].add(0);
                } else if (x == 'M') {
                    arr[num].add(1);
                } else {
                    arr[num].add(2);
                } 
            }
        }
        
        int count = 0;
        for (int i = 0; i < 3; i++) {
            while (!size[i].isEmpty()) {
                if (!arr[size[i].get(0)].isEmpty()) {
                    Iterator<Integer> iterator = arr[size[i].get(0)].iterator();
                    while (iterator.hasNext()) {
                        int adj = iterator.next();
                        if (adj <= i) {
                            count++;
                            iterator.remove();
                            break;
                        }
                    }
                }
                size[i].remove(0);
            }
        }
        
        System.out.println(count);
        
    }
}