作业
1. 请用代码验证"name"是否在字典的键中
info = {"name": "王刚", "hobby": "铁锤", "age": 18} # print("name" in info) # print("name" in info.keys()) # True
2. 循环提示用户输入,并将输入内容追加到列表中,如果输入N或者n则停止循环
例如: ['sdavav', 'nhft', 'lk', 'wewe']
l1 = [] while 1: content = input(">>>") if content.upper() == "N": break l1.append(content) print(l1)
3. 循环提示用户输入,并将输入内容追加到字典中,如果输入N或者n则停止循环
例如: [{"name": "太白", "password": 123}, {"name": "sff", "password": 236}, {"name": "rg", "password": 568},...]
li = [] # dic = dict() while 1: user_name = input("请输入用户名:") if user_name.upper() == "N": break password = input("请输入密码:") dic = dict() dic["name"] = user_name dic["password"] = password li.append(dic) print(li)
4. 看代码写结果并解释原因
# v1 = {"k1": "v1", "k2": [1, 2, 3]} # v2 = {"k1": "v1", "k2": [1, 2, 3]} # result1 = v1 == v2 # result2 = v1 is v2 # print(result1) # True # print(result2) # False
5. 看代码写结果并解释原因
变量指向的是真实的数据
# v1 = "人生苦短,用python" # v2 = [1, 2, 3, v1] # # v1 = "人生苦短,用毛线python" # print(v2) # [1, 2, 3, '人生苦短,用python'] # 理解成变量的赋值 例如 a = 10, b = a, c = b, b = 15 # info = [1, 2, 3] # userinfo = {"account": info, "num": info } # info.append(9) # print(userinfo) # {'account': [1, 2, 3, 9], 'num': [1, 2, 3, 9]} # info = [1, 2, 3] # userinfo = {"account": info, "num": info } # info = "好多题" # print(userinfo) # {'account': [1, 2, 3], 'num': [1, 2, 3]} # info = [1, 2, 3] # userinfo = [info, info ,info , info] # info[0] = "好嗨哟" # print(info, userinfo) # ['好嗨哟', 2, 3] [['好嗨哟', 2, 3], ['好嗨哟', 2, 3], ['好嗨哟', 2, 3], ['好嗨哟', 2, 3]] # info = [1, 2, 3] # userinfo = [info, info ,info , info] # userinfo[2][0] = "shut up" # print(info, userinfo) # ['shut up', 2, 3] [['shut up', 2, 3], ['shut up', 2, 3], ['shut up', 2, 3], ['shut up', 2, 3]] # data_list = [] # data = {} # for i in range(5): # data["user"] = i # data_list.append(data) # print(data) # {'user': 4} # print(data_list) # [{'user': 4}, {'user': 4}, {'user': 4}, {'user': 4}, {'user': 4}]