def get_forward_char(node, count):
    r = ''
    while True:
        if (not node):
            return r[::(- 1)]
        r += str(node)[::(- 1)]
        if (len(r) >= count):
            return r[::(- 1)][(- count):]
        node = node.last
def get_forward_char(node, count):
    r = 
    while True:
        if (not node):
            return r[::(- 1)]
        r += str(node)[::(- 1)]
        if (len(r) >= count):
            return r[::(- 1)][(- count):]
        node = node.last