li = ['alex', 'eric', 'rain']
v = "_".join(li)
print(v)

li = ["alec", " aric", "Alex", "Tony", "rain"]  # 列表

tu = ("alec", " aric", "Alex", "Tony", "rain")  # 元组

dic = {'k1': "alex", 'k2': ' aric', "k3": "Alex", "k4": "Tony"}  # 字典

tu_li = list(tu)
dic_li = list(dic.values())
list = li + tu_li + dic_lifor i in list:m = i.strip()# startswith查看开头字符，endswith查看结尾字符if(m.startswith('a') or m.startswith('A') and m.endswith('c')):print(m)

# 1
print(len(li))
# 2
li.append("seven")
print(li)
# 3
li.insert(0,'Tony')
print(li)
# 4
li[1] = 'Kelly'
print(li)
# 5
li.remove('eric')
print(li)
# 6
li.pop(1)
print(li)
# 7
li.pop(2)
print(li)
# 8
li = ['alex', 'eric', 'rain']
del li[1:3]
print(li)
# 9
li = ['alex', 'eric', 'rain']
li.reverse()
print(li)
# 10
li = ['alex', 'eric', 'rain']
for i in range(len(li)):print(i)
# 11
li = ['alex', 'eric', 'rain']
for m,n in enumerate(li,100):print(m,n)
# 12
for i in li:print(i)

print(li[2][1][1])li[2][2] = "ALL"
print(li)

print(len(tu))print(tu[1])print(tu[0:2])for i in tu:print(i)for m in range(len(tu)):print(m)for n,k in enumerate(tu,10):print(n,k)

# 1
for i in dic.keys():print(i)
# 2
for j in dic.values():print(j)
# 3
for i,j in dic.items():print(i,j)
# 4
dic["k4"] = "v4"
print(dic)
# 5
dic["k1"] = "alex"
print(dic)
# 6
dic["k3"].append(44)
print(dic)
# 7
dic["k3"].insert(0,18)
print(dic)

# 1
s = "alex"
s_list = list(s)
print(s_list)
# 2
s = "alex"
s_tuple = tuple(s)
print(s_tuple)
# 3
li = ["alex", "seven"]
li_tuple = tuple(li)
print(li_tuple)
# 4
tu = ('Alex', "seven")
tu_list = list(tu)
print(tu_list)
# 5
li = ["alex", "seven"]
li_dict = {}
for m,n in enumerate(li,10):li_dict[m] = nprint(li_dict)

li = [11,22,33,44,55,66,77,88,99,90]
li.sort()  # 排序
list1 = []
list2 = []
for i in li :if i < 66:list1.append(i)elif i > 66:list2.append(i)else:pass
dic = {"k1": list1,"k2": list2}
print(dic)

print("商品列表，用户输入序号，显示用户选中的商品".center(25,'-'))
li = ["手机", "电脑", '鼠标垫', '游艇']
for i,num in enumerate(li,1):print(i,num)
# 添加商品
choice = input("y=yes,n=no]  是否添加商品:".rjust(20,'-'))
if choice == "y" or choice == "Y":good = input("需要添加的商品".rjust(20,'-'))li.append(good)for i,num in enumerate(li,1):print(i,num)
elif choice =='n' or choice == "N":pass
else:print("请输入正确的选项")choice_Item = input("[q=quit]  查看序号对应商品，按q退出！")
if choice_Item.isdigit() and int(choice_Item) <= len(li):print(li[int(choice_Item)-1])

china = {'北京':{'海淀':{},'朝阳':{},'东城':{}},'湖北':{'武汉':{},'荆门':{},'宜昌':{}}
}current_layer = china # 当前层
layers = []
tag = Truewhile tag:# 一级菜单for k in current_layer:print(k)choice = input(">:").strip()# 二级菜单if choice in current_layer:# 进入下一级菜单，保存当前菜单
        layers.append(current_layer)# 二级菜单赋给当前层current_layer = current_layer[choice]elif choice == "back":if len(layers) != 0:# pop删除列表最后一个元素，并返回删除后最后一个元素current_layer = layers.pop()else:print("已经是最顶层目录！")elif choice == "add":add_node = input("在当前目录下添加节点：")current_layer[add_node] = {}elif choice == "exit":tag = Falseprint("good bye!")else:continue

set1 = set(l1)
set2 = set(l2)p1 = set1 & set2
print(p1)p2 = set1.difference(set2)
print(p2)p3 = set2.difference(set1)
print(p3)p4 = set1.union(set2).difference(set1 & set2)
print(p4)

#左下三角格式输出九九乘法表
for i in range(1,10):for j in range(1,i+1):print("%d*%d=%2d" % (i,j,i*j),end=" ")print (" ")

sum_prime = 0
for i in range(2,101):n = 0for j in range(2,i-1):if i % j == 0:n = 1breakif n == 0:sum_prime += i
print(sum_prime)

li = [1,3,2,7,6,23,41,24,33,85,56]
for i in range(0,len(li)):for j in range(i+1,len(li)):if li[i] > li[j]:li[i], li[j] = li[j], li[i]print(li)