class TreeNode:
    def __init__(self, label):
        self.label = label
        self.left = None
        self.right = None

def build_tree(height, current_label):
    if height < 0:
        return None

    node = TreeNode(current_label[0])
    current_label[0] -= 1
    return node

def build_path_tree(root, height, road, current_label):
    node = root
    for move in road:
        if move == 'L':
            if node.left is None:
                node.left = build_tree(height - 1, current_label)
            node = node.left
            height -= 1
        elif move == 'R':
            if node.right is None:
                node.right = build_tree(height - 1, current_label)
            node = node.right
            height -= 1
    return node

def search_node(height, road=""):
    total_nodes = (2 ** (height + 1)) - 1
    current_label = [total_nodes]
    root = build_tree(height, current_label)

    if not road:
        return root.label

    target_node = build_path_tree(root, height, road, current_label)
    return target_node.label

def main():
    line = input().strip()
    parts = line.split()
    height = int(parts[0])
    road = parts[1] if len(parts) > 1 else ""

    print(search_node(height, road))

main()