import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

class BinarySearchTree {
    class Node {
        int element;
        Node left;
        Node right;

        Node(int x) {
            element = x;
        }
    }

    Node root;

    void insert(int x) {
        root = insert(root, x);
    }

    Node insert(Node v, int x) {
        if (v == null) {
            return new Node(x);
        } else if (x < v.element) {
            v.left = insert(v.left, x);
        } else if (x > v.element) {
            v.right = insert(v.right, x);
        }
        return v;
    }

    int minHeight(Node v) {
        if (v == null) {
            return -1;
        }
        return 1 + Math.min(minHeight(v.left), minHeight(v.right));
    }

    int height(Node v) {
        if (v == null) {
            return -1;
        }
        return 1 + Math.max(height(v.left), height(v.right));
    }

    boolean isBalanced() {
        return height(root) - minHeight(root) <= 1;
    }
}

class BalanceChecker {
    public static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        BinarySearchTree tree = new BinarySearchTree();

        for (String line = br.readLine(); line != null; line = br.readLine()) {
            int x = Integer.parseInt(line);
            tree.insert(x);
        }
        if (tree.isBalanced()) {
            System.out.println("Dette treet ser balansert ut!");
        } else {
            System.out.println("Dette treet ser ikke helt balansert ut... pr?v igjen!");
        }
    }
}