python基础五
1 字典dic = {'k1':"v1",'k2'="v2","k3":[11,22,33]}
dic = {'k1':"v1", 'k2':"v2", "k3":[11,22,33]} # 1)循环输出所有的key # for i in dic.keys(): # print(i) # 2)循环输出所有的value # for i in dic.values(): # print(i) # 3)循环所有的key与value # for k,v in dic.items(): # print(k,v) # 4)在字典中添加一个键值对,‘k4’:'v4' # dic['k4']='v4' # dic.setdefault('k4','v4') # 5)请在修改字典中‘k1’对应的值为‘alex’ # 1.dic['k1']='alex' # 2.dic1 = {'k1':'alex'} # dic.update(dic1) # 6)在k3对应的值中追加一个元素44 # dic['k3'].append(44) # 7)在k3对应的值的第一个位置插入一个元素18 #dic['k3'].insert(0,'18')
2)元素分类 有如下值li=[11,22,33,44,55,66,77,88,99,90],将所有大于等于66的值保存至
字典的第一个key中,将小于66的值保存至第二个key值中
# li=[11,22,33,44,55,66,77,88,99,90] # dic = {'key1':[],'key2':[]} # for i in li : # if i >= 66: # dic['key1'].append(i) # else: # dic['key2'].append(i) # print(dic)
3)输出商品列表,用户输入序号,显示用户选中的商品
商品li = ["手机","电脑","鼠标垫","游艇"]
要求: 1:页面显示 序号+商品名称 如:
1 手机
2 电脑
...
2:用户输入选择的商品序号,然后打印商品名称
3:如果用户输入的商品序号有误,则提示输入错误
4:用户输入Q或q,退出程序
li = ["手机","电脑","鼠标垫","游艇"] msg = ''' 1:页面显示 2:查询商品信息 Q:退出系统 ''' while 1: operate = input("请输入您需要的操作"+msg) if operate == '1': for i in li : print(li.index(i)+1,i) elif operate == '2': order = int(input("请输入商品序号"))-1 if order > 3 or order<1: print("序号有误") break else : print(order+1,li[order]) elif operate.lower() =='q': break else: operate = input("输入有误,重新输入")