import java.util.Scanner;

public class BinaryTreeLabel {

    static class TreeNode {
        int label;
        TreeNode left, right;

        TreeNode(int label) {
            this.label = label;
            this.left = this.right = null;
        }
    }

    public static TreeNode buildTree(int height) {
        int totalNodes = (1 << (height + 1)) - 1;
        int[] currentLabel = {totalNodes};
        return buildTreeRecursively(height, currentLabel);
    }

    private static TreeNode buildTreeRecursively(int height, int[] currentLabel) {
        if (height < 0) {
            return null;
        }
        TreeNode node = new TreeNode(currentLabel[0]--);
        node.right = buildTreeRecursively(height - 1, currentLabel);
        node.left = buildTreeRecursively(height - 1, currentLabel);
        return node;
    }

    public static int findLabel(TreeNode root, String path) {
        TreeNode currentNode = root;
        for (int i = 0; i < path.length(); i++) {
            if (path.charAt(i) == 'L') {
                currentNode = currentNode.left;
            } else if (path.charAt(i) == 'R') {
                currentNode = currentNode.right;
            }
        }
        return currentNode.label;
    }

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        String inputLine = scanner.nextLine().strip();
        String[] parts = inputLine.split(" ");
        int height = Integer.parseInt(parts[0]);
        String path = parts.length > 1 ? parts[1] : "";
        TreeNode root = buildTree(height);
        int result = findLabel(root, path);
        System.out.println(result);
        scanner.close();
    }
}