def infix_to_suffix(self):
op_stack = Stack()
for element in self.exp_elements_infix:
if element == Const.Pow or element == Const.LeftBracket:
# 左括号和乘方必定入栈
op_stack.push(element)
elif element == Const.Mul or element == Const.Div:
# 乘除法需要弹出乘方与乘除
while op_stack.size() > 0 and \
(op_stack.peek() == Const.Mul or op_stack.peek() == Const.Div or op_stack.peek() == Const.Pow):
op = op_stack.pop()
self.exp_elements_suffix.append(op)
op_stack.push(element)
elif element == Const.Plus or element == Const.Sub:
while op_stack.size() > 0 and (op_stack.peek() !=
Const.LeftBracket):
op = op_stack.pop()
self.exp_elements_suffix.append(op)
op_stack.push(element)
elif element == Const.RightBracket:
while op_stack.peek() != Const.LeftBracket:
op = op_stack.pop()
self.exp_elements_suffix.append(op)
op_stack.pop()
else:
self.exp_elements_suffix.append(element)
while op_stack.size() > 0:
self.exp_elements_suffix.append(op_stack.pop())
class Pager(View, ABC):
cache_size = 10
# 默认 请求页数 1
# 缓存页面 默认为 10
def __init__(self, template):
super().__init__(template)
self.history_stack = Stack()
self.pager = 1
def on_destroy(self):
self.data = None
def next_pager(self):
self.pager = self.pager + 1
# 缓存上一页的数据
if self.history_stack.size() > self.cache_size:
# 缓存页数据出栈
self.history_stack.pop()
self.history_stack.push(self.data)
self.data = self.get_data()
# 重新打印当前内
def up_pager(self):
# 缓存队列
self.pager = self.pager - 1
# 如果前一页有缓存 不为空
if not self.history_stack.size() == 0:
self.data = self.history_stack.pop()
else:
if self.pager < 2:
self.pager = 1
self.data = self.get_data()
def get_data(self):
self.show_loading()
return json.loads(get_plate_info(self.id, self.pager))
def show_loading(self):
self.print_text("加载中...")
def handler_input(self, ip):
"""
:param ip: 输入
:return: 是否传递输入给 APP
"""
if ip == Config.instance.pg_down:
self.next_pager()
return True
if ip == Config.instance.pg_up:
self.up_pager()
return True
if ip.startswith(Config.instance.prefix_re):
self.do_reply(ip[len(Config.instance.prefix_re):])
return True
if ip == Config.instance.pg_re:
self.refresh()
return True
if is_number(ip):
return self.index_type(ip)
def do_reply(self, text):
"""
text 输入 页
:param text:
:return:
"""
Route.instance.show_toast(post_string(self.id, text))
def index_type(self, ip):
Route.instance.push({"name": "info", "parm": self.data[int(ip)]["id"]})
return True
def on_creat(self):
self.id = Route.instance.cur_intent["parm"]
def test_empty_stack():
s = Stack()
assert s.size() == 0
assert len(s) == 0