Main.java - master - Klimchik/hm2-alg

Main.java
64 строки2 KB
Klimchik
update: Main.java
15 фев 2026, 13:46
15 фев 2026, 13:46cad2514
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 + 5]);
        System.out.println("Iterative = " + iterative + " | Recursive = " + recursive);
        System.out.println();
    }

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

        return calculateValue(index, startNumbers, memory);
    }

    private static int calculateValue(int index, int[] startNumbers, int[] memory) {
        if (index < 4) {
            return startNumbers[index];
        }

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

        int prev = calculateValue(index - 1, startNumbers, memory);
        int prePrePrev = calculateValue(index - 3, startNumbers, memory);
        
        int result = (prev * prePrePrev) % 10 + 1;

        memory[index] = 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;
            int prev = numbers.get(index - 1);
            int prePrePrev = numbers.get(index - 3);
            numbers.add((prev * prePrePrev) % 10 + 1);
        }

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