import java.util.*;

public class Main {

    public static int lyhinReitti(int[][] kartta) {
        Node[][] nodes = new Node[kartta.length + 1][kartta[0].length + 1];
        Node alku = new Node(false);

        for (int x = 1; x < kartta.length - 1; x++) {
            for (int y = 1; y < kartta[0].length - 1; y++) {
                if (kartta[x][y] == 0 || kartta[x][y] == 2) {
                    Node newNode = new Node(false);

                    if (kartta[x][y] == 2) {
                        alku = newNode;
                    }


                    nodes[x][y] = newNode;
                } else if (kartta[x][y] == 3) {
                    nodes[x][y] = new Node(true);
                }
            }
        }

        for (int x = 1; x < kartta.length - 1; x++) {
            for (int y = 1; y < kartta[0].length - 1; y++) {
                if (nodes[x][y] != null) {
                    if (nodes[x - 1][y] != null) {
                        nodes[x][y].routes.add(nodes[x - 1][y]);
                    }

                    if (nodes[x + 1][y] != null) {
                        nodes[x][y].routes.add(nodes[x + 1][y]);
                    }

                    if (nodes[x][y - 1] != null) {
                        nodes[x][y].routes.add(nodes[x][y - 1]);
                    }

                    if (nodes[x][y + 1] != null) {
                        nodes[x][y].routes.add(nodes[x][y + 1]);
                    }
                }
            }
        }

        ArrayDeque<Node> current = new ArrayDeque<>();
        current.add(alku);

        while (!current.isEmpty()) {
            Node currentNode = current.poll();

            if (currentNode.goal) {
                return currentNode.pituus;
            }

            currentNode.visited = true;

            for (Node nextNode : currentNode.routes) {
                if (!nextNode.visited) {
                    nextNode.pituus = currentNode.pituus + 1;
                    current.add(nextNode);
                }
            }
        }

        return -1;
    }

    public static void main(String[] args) {
        int[][] kartta = {{1, 1, 1, 1, 1, 1, 1, 1},
        {1, 0, 3, 1, 0, 0, 0, 1},
        {1, 0, 1, 1, 0, 1, 0, 1},
        {1, 0, 0, 0, 0, 2, 0, 1},
        {1, 1, 1, 1, 1, 1, 1, 1}};
        System.out.println(lyhinReitti(kartta));
    }
}



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import java.util.ArrayList;

public class Node {

    ArrayList<Node> routes;
    boolean visited;
    boolean goal;
    int pituus;

    public Node(boolean goal) {
        this.routes = new ArrayList<>();
        this.visited = false;
        this.goal = goal;
        this.pituus = 0;
    }
}