class Task220925 {
    public static void main(String[] args) {
        String input = "   ";
        String result = StringUtils.safeTrim(input);
        System.out.println("'" + result + "'");
        System.out.println("isEmpty: " + StringUtils.isEmpty(result));
    }
}

public class StringUtils {
    // KISS
    public static boolean isEmpty(String s) {
        return s == null || s.trim().isEmpty();
    }
    
    // YAGNI
    public static String toTitleCase(String s) {
        if (isEmpty(s)) return s;
        return Character.toUpperCase(s.charAt(0)) + s.substring(1).toLowerCase();
    }
    
    // DRY
    public static String safeTrim(String s) {
        return isEmpty(s) ? "" : s.trim();
    }
}

import java.util.Random;

public class Task230925 {
    public static void main(String[] args) {
        Random rand1 = new Random(42);
        Random rand2 = new Random(42);

        System.out.println(rand1.nextInt(100) == rand2.nextInt(100));
    }
}

import java.util.HashMap;

public class Task240925 {
    public static void main(String[] args) {
        HashMap<String, Integer> map = new HashMap<>();
        map.put("a", 1);
        map.put(new String("a"), 2);
        
        System.out.println(map.size());
        System.out.println(map.get("a"));
    }
}

import java.util.function.Function;

public class Task250925 {
    public static void main(String[] args) {
        Function<Integer, Integer> plus5 = x -> x + 5;
        Function<Integer, Integer> times2 = x -> x * 2;
        
        Function<Integer, Integer> composed = plus5.compose(times2);
        System.out.println(composed.apply(3));
    }
}

public class Task260925 {
    public static void main(String[] args) {
        String a = "hello";
        String b = "he" + "llo";
        String c = "he";
        String d = "llo";
        String e = c + d;
        String f = (c + d).intern();
        
        System.out.print((a == b) + " ");
        System.out.print((a == e) + " ");
        System.out.print((a == f) + " ");
        System.out.print(a.equals(e));
    }
}

public class Task290925 {
    public static void main(String[] args) {
        Boolean a = true;
        Boolean b = true;
        Boolean c = new Boolean(true);
        
        System.out.println((a == b) + " " + (a == c));
    }
}

import java.util.*;

public class Task300925 {
    public static void main(String[] args) {
        Set<Short> set = new HashSet<>();
        
        for (short i = 0; i < 10; i++) {
            set.add(i);
            set.remove(i - 1);
        }
        
        System.out.println(set.size());
    }
}

import java.util.*;

public class Task011025 {
    public static void main(String[] args) {
        Queue<Integer> queue = new LinkedList<>();
        queue.offer(1);
        queue.offer(2);
        queue.offer(3);
        
        ((LinkedList<Integer>) queue).removeLast();
        queue.poll();
        
        System.out.println(queue.peek());
    }
}

import java.util.*;

public class Task021025 {
    public static void main(String[] args) {
        Map<String, Integer> map1 = new HashMap<>();
        Map<String, Integer> map2 = new HashMap<>();
        
        map1.put("a", 1);
        map1.put("b", 1);
        
        map2.put("b", 1);
        map2.put("a", 1);
        
        System.out.println(map1.equals(map2));
        System.out.println(Objects.equals(map1, map2));
    }
}

import java.util.LinkedList;
import java.util.List;

public class Task031025 {
    public static void main(String[] args) {
        List<String> list = new LinkedList<>();
        list.add("A");
        list.add("B");
        list.add(1, "C");
        list.remove(0);
        list.remove(1);
        System.out.println(list);
    }
}