src/Main.java - master - itokar98/HomeWorkAlgoDYN

src/Main.java
60 строк2 KB
Ilya Tokar
firstCommit
23 авг 2025, 15:34
23 авг 2025, 15:342a1acfd
import java.util.ArrayList;
import java.util.List;

public class Main {

    public static void main(String[] args) {
        compare(1);
        compare(2);
        compare(5);
        compare(15);
    }

    public static void compare(int day) {
        System.out.println("=== Day " + day + " ===");
        int[] startNumbers = { 21, 1, 20, 23 };
        int iterative = chooseHobbyIterative(startNumbers, day);
        int recursive = chooseHobbyRecursive(startNumbers, day, new int[day+4]);
        System.out.println("Iterative = " + iterative + " | Recursive = " + recursive);
        System.out.println();
    }

    public static int chooseHobbyRecursive(int[] startNumbers, int day, int[] memory) {
        int dayIndex = day + 3;

        if (dayIndex < 4) {
            return startNumbers[dayIndex];
        }

        if (memory[dayIndex] != 0) {
            return memory[dayIndex];
        }

        int prev = chooseHobbyRecursive(startNumbers, day-1, memory);
        int prevPrevPrev = chooseHobbyRecursive(startNumbers, day-3, memory);

        int result = (prev * prevPrevPrev) % 10 + 1;

        memory[dayIndex] = result;

        return  result;
    }

    public static int chooseHobbyIterative(int[] startNumbers, int day) {
        List<Integer> numbers = new ArrayList<>();

        numbers.add(startNumbers[0]);
        numbers.add(startNumbers[1]);
        numbers.add(startNumbers[2]);
        numbers.add(startNumbers[3]);

        for (int d = 0; d < day; d++) {
            int index = d + 4; // индексы дней в массиве сдвинуты на 4
            int prev = numbers.get(index - 1); // предыдущее значение
            int prePrePrev = numbers.get(index - 3); // пре-пре-предыдущее значение
            numbers.add((prev * prePrePrev) % 10 + 1);
        }

        return numbers.get(numbers.size() - 1);
    }
}