import java.util.ArrayList;

public class ArrayListProbs{
    public static void main(String[] args){
        ArrayList<String> list = new ArrayList<String>();
        list.add("cat");
        list.add("dog");
        list.add("mouse");
        list.add("rat");
        list.add("frog");
        System.out.println(list);
        System.out.println(numWordsOfLength(list,3));
        System.out.println(numWordsOfLength(list,4));
        System.out.println(numWordsOfLength(list,2));
        removeWordsOfLength(list, 3);
        System.out.println(list);
    }

    public static int numWordsOfLength(ArrayList<String> arr, int len){
        int count = 0;

        return count;
    }


    public static void removeWordsOfLength(ArrayList<String> arr, int len){
  
        
        return;
    }
}