#元组相对列表来说不同之处是只读不可写 读操作和列表一致
 letter_tuple = ('a','b','c','d');
 print(letter_tuple[0]);#result:a
 print(letter_tuple[0:3]);#result:['a', 'b', 'c']
 print(letter_tuple[3::-1]);#result:['c', 'b', 'a']

 addressDic = {'湖北':['武汉','襄阳'],'湖南':['长沙','岳阳']}
 for province in addressDic:
     cityList = addressDic[province];
     print(province,end = ":");
     for city in cityList:
         print(city,end = ";");
     print();
 #result:
     # 湖北: 武汉;襄阳;
     # 湖南: 长沙;岳阳;

 letterStr = 'abcdefg';
 #重复输出
 print(letterStr*2);#result:abcdefgabcdefg
 #切片
 print(letterStr[2:]);#result:cdefg
 #判断是否存在
 print('abc' in letterStr);#result:True
 #格式化输出
 print('abcd%s'%'efg');

 #string的内置方法
 #获取元素个数
 print(letterStr.count('c'));#result:1
 #字符串首字母大写
 print(letterStr.capitalize());#result:Abcdefg
 #指定长度居中
 print(letterStr.center(20,'-'));#result:------abcdefg-------
 #是否以指定元素结尾
 print(letterStr.endswith("g"));#result:True
 #是否以指定元素开头
 print(letterStr.startswith("a"));#result:True
 #指定tab空格长度
 print("a\tb".expandtabs(tabsize=10));#result:a         b
 #返回指定第一个元素索引值
 print(letterStr.find('c'));#result:2
 #格式化
 print("hello {next}".format(next="world"));#result:hello world
 print("name:{name};{age} years old".format_map({"name":"zhangsan","age":12}));#result:name:zhangsan;12 years old
 #返回指定元素索引 不存在时会报错
 print(letterStr.find('c'));#result:2
 #判断只包含数字或字母
 print("deqad#".isalnum());#result:False;
 #判断是否是整形数字
 '.isdigit());#result:True
 #判断是否不是非法命名
 print("123a".isidentifier());#result:False
 #判断是否小写
 print(letterStr.islower());#result:True
 #判断是否大写
 print(letterStr.isupper());#result:False
 #判断是否是个空格
 print(letterStr.isspace());#result:False
 #判断是否每个单词首字母大写
 print(letterStr.istitle())#result:False
 #转小写
 print(letterStr.lower());#result:abcdefg
 #转大写
 print(letterStr.upper());#result:ABCDEFG
 #大小写反转
 print(letterStr.swapcase());#result:ABCDEFG
 #左填充
 print(letterStr.ljust(20,'*'));#abcdefg*************
 #右填充
 print(letterStr.rjust(20,'*'));#*************abcdefg
 #去首尾空白字符
 print("  ade  \n".strip());#result:ade
 #去首部空白字符
 print("  ade  ".lstrip());#result:ade
 #去尾部空白字符
 print("  ade  \n".rstrip());#result:  ade
 #替换
 print(letterStr.replace('g','ghi'));#result:abcdefghi
 #从右往左查找 返回实际位置
 print("acbbbbcss".rfind('c'));#result:6
 #切割字符串 返回列表
 print(letterStr.split('d'));#result:['abc', 'efg']
 #字符串内每个单词首字母大写
 print('hello world'.title());#result:Hello World

 import queue

 q = queue.Queue()
 q.put(1)
 q.put(2)
 q.put(3)
 print(q.qsize())  # 3 查看队列元素个数

 print(q.get())  # 阻塞

 mainDic = {
     'a1':{
         'a1b1':{
             'a1b1c1':{},
             'a1b1c2':{},
             'a1b1c3':{}
         },
         'a1b2':{
             'a1b2c1': {},
             'a1b2c2': {},
             'a1b2c3': {}
         },
         'a1b3':{
             'a1b3c1': {},
             'a1b3c2': {},
             'a1b3c3': {}
         }
     },
     'a2':{
         'a2b1': {
             'a2b1c1': {},
             'a2b1c2': {},
             'a2b1c3': {}
         },
         'a2b2': {
             'a2b2c1': {},
             'a2b2c2': {},
             'a2b2c3': {}
         },
         'a2b3': {
             'a2b3c1': {},
             'a2b3c2': {},
             'a2b3c3': {}
         }
     },
     'a3':{
         'a3b1': {
             'a3b1c1': {},
             'a3b1c2': {},
             'a3b1c3': {}
         },
         'a3b2': {
             'a3b2c1': {},
             'a3b2c2': {},
             'a3b2c3': {}
         },
         'a3b3': {
             'a3b3c1': {},
             'a3b3c2': {},
             'a3b3c3': {}
         }
     }
 };
 currentLayer = mainDic;
 parentLayers = [];
 while True:
     for item in currentLayer:
         print(item);
     choose = input('input your choose:');
     if(choose in currentLayer):
         if not currentLayer[choose]:
             print('last layer');
             continue;
         parentLayers.append(currentLayer);
         currentLayer = currentLayer[choose];
     elif choose=='e':
         currentLayer = parentLayers.pop();
     elif choose=='exit':
         break;
     else:
         print('该项不存在');

 #result:
     # >>a1
     # >>a2
     # >>a3
     # >>input your choose:a2
     # >>a2b1
     # >>a2b2
     # >>a2b3
     # >>input your choose:a2b2
     # >>a2b2c1
     # >>a2b2c2
     # >>a2b2c3
     # >>input your choose:e
     # >>a2b1
     # >>a2b2
     # >>a2b3
     # >>input your choose:e
     # >>a1
     # >>a2
     # >>a3
     # >>input your choose:exit

 a,b = [1,2];
 print(a);#result:1
 print(b);#result:2

letter_tuple = ['a','b','c','d','e'];
for index,value in enumerate(letter_tuple,1):
    print(index,value);
#result:
    # (1, 1)
    # (2, 2)
    # (3, 3)
    # (4, 4)
    # (5, 5)

 letterStr = 'abcdefg';
 letterList = ['a','b','c','d','e','f','g'];
 print(len(letterStr));#result:7
 print(len(letterList));#result:7

 list = [];
 if list:print('True');
 else:print('False');
 #result:False;
 list.append(1);
 if list:print('True');
 else:print('False')
 #result:True