Python-day7

1、for-in  else

for i in range(3):
    psw=input('请输入密码：')
    if psw=='123123':
        print('密码正确')
        break
    else:
        print('密码错误')
        i+=1
else:
    print('三次密码均错误')

2、while   else

i=0
while i<3:
    psw=input('请输入密码：')
    if psw=='123123':
        print('密码正确')
        break
    else:
        print('密码错误')
        i+=1
else:
    print('三次密码均错误')

3、嵌套循环

for i in range(1,4):
    for j in range(1, 5):
        print('*',end=('\t'))
        j+=1
    i+=1
    print()

for i in range(1,10):
    for j in range(1,i+1):
        print(i,'*',j,'=',i*j,end=('\t'))
        j+=1
    i+=1
    print()

4、列表

#获取索引、指定元素、切片、添加操作
list=['you','are','the','best',666]
print(list[3])
print(list.index('the'))
print(list.index(666,1,5))
print(list[1:4:2])
print('you' in list)
list2=['I','am','a','girl']
list.append(list2)
print(list)
list.extend(list2)
print(list)
list.insert(8,'OK')
print(list)
list.insert(9,list2)
list[1:4]=list2
print(list)

#列表元素删除
list=['you','are','the','best',666]
list2=['you',666,888,999,111]
list.remove(666)
print(list)
list.pop(3)
print(list)
list.pop()
print(list)
list2[2:4]=[]
print(list2)
list.clear()
print(list)
del list
print(list)

#改
list=['you','are','the','best',666]
list[4]='aaaa'
print(list)
list[1:5]=[1,2,3,4]
print(list)

#排序
list=[1,2,3,46,7,8,89]
list.sort()
print(list)
list.sort(reverse=True)
print(list)

#生成列表[2,4,6,8,10]
list=[i*2 for i in range(1,6)]
print(list)