public class Task100925 {
    public static void main(String[] args) {
        int[] a = {1, 2, 3};
        int[] b = a;
        b[0] = 10;
        System.out.println(a[0]);
    }
}

public class Task110925 {
    public static void main(String[] args) {
        final int x = 10;
        final int y = getValue();
        
        System.out.println(x + y);
    }
    
    static int getValue() {
        return 20;
    }
}

public class Task120925 {
    public static void main(String[] args) {
        double a = 0.1;
        double b = 0.2;
        double c = 0.3;
        
        System.out.println(a + b == c);
    }
}

public class Task150925 {
    static int x = 5;
    
    static {
        x = 10;
        y = 20;
    }
    
    static int y = 15;
    
    public static void main(String[] args) {
        System.out.println(x + " " + y);
    }
}

import java.util.concurrent.*;

public class Task160925 {
    public static void main(String[] args) throws Exception {
        ExecutorService executor = Executors.newSingleThreadExecutor();
        Future<String> future = executor.submit(() -> {
            Thread.sleep(1000);
            return "Done";
        });
        
        System.out.println(future.get(500, TimeUnit.MILLISECONDS));
        executor.shutdown();
    }
}

enum Status {
    ACTIVE, INACTIVE;
    
    Status() {
        System.out.print(this.name() + " ");
    }
}

public class Task170925 {
    public static void main(String[] args) {
        System.out.print("Start ");
        Status status = Status.ACTIVE;
        System.out.print("End");
    }
}

import java.util.HashSet;
import java.util.Set;

public class Task180925 {
    public static void main(String[] args) {
        Point p1 = new Point(1, 2);
        Point p2 = new Point(1, 3);
        Set<Point> set = new HashSet<>();
        set.add(p1);
        set.add(p2);
        System.out.println(set.size());
    }

    public record Point(int x, int y) {
        public Point {
            if (x < 0) throw new IllegalArgumentException("x < 0");
            if (y < 0) throw new IllegalArgumentException("y < 0");
        }

        public boolean equals(Object o) {
            return o instanceof Point p && p.x == x;
        }

        public int hashCode() {
            return x;
        }
    }
}

class Animal190925 {
    public String speak() {
        return "Some sound";
    }
}

class Dog190925 extends Animal190925 {
    public String speak() {
        return "Woof";
    }
    
    public String fetch() {
        return "Fetching stick";
    }
}

public class Task190925 {
    public static void main(String[] args) {
        Animal190925 myAnimal = new Dog190925();
        System.out.println(myAnimal.speak());
        System.out.println(myAnimal.fetch());
    }
}

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));
    }
}