代码: ''' 用户与程序交互: input( )输入 print()输出 username=input('请输入提示信息') ''' username=input('请输入用户名:') print(username) password = input('请输入密码:') print(password) # 如果 # username == 'tank ' True # and: 左右两边的条件都为了True才为True,否则为False # password == '123' True # if 条件判断:如果条件判断 == True,执行if下的代码 if username =='tank' and password == '123': # False and True ---》 False print('登录成功') else: print('登陆失败') # 占位符: %s str1 = '很帅' print('tank%s' % (str1,)) # tank很帅 str2 = '信念与我同在,我将无坚不摧' print('自信养成记1: %s' % (str2, )) price1 = input('请输入该用户当月扣费月租') all = input('请输入该用户当前余额: ') print('亲爱的移动用户,您当前月租为[%s]元,账户余额为[%s]元 ' % (price1,all)) # - 算数运算符 print(1+1) # 2 n1 = 1 # n1 =n1 + 1 # n1 += 1 # print(n1) # 2 n1 += 1 # 赋值运算符: -= print(10 - 1) # 9 # *= print(12 * 12) # 144 print(11 / 3) # 3.666... print(11 // 3) # 3 print(11 % 3) # 2 # 比较运算符 print(1 == 2) # False print(1 >2) # False print(1 < 2) # True print(1 >=2 ) # False print(1 <= 2) # Ture # is:比较两个变量的id是否相等 x = 10 print(id(x) == id(x) ) # True print(x is x) # True #逻辑运算符 # and: 左右两边的条件都为了True才为True,否则为False print(x == 1 and x == 10) # False print(x == 10 and x == 10) # True # or:判断两边的条件是否成立,其1成立则为Ture print(x == 10 or x == 1) # True # not:取反 print(x == 10) # True print(not x == 10) # False # no-->and-->or # True or Fslse print(not x == 1 or x == 10 and x == 20) # True # 链式赋值 n = 10 y = n z = y print(n,y,z) n = y = z = 10 print(n,y,z) #交叉赋值 x = 10 y = 20 # x与y的值互换 # x = 20 y = 10 z = x # 10 x = y # 20 y = z # 10 x = 10 y = 20 # 10, 20 = y = 10, x=20 x, y = y, x print(x,y) # 20 10 # 解压缩赋值 # 0 1 2 list1 = [1,2,3] x = list1[0] y = list1[1] z = list1[2] print(x,y,z) # 1 2 3 x,y,z = list1 print(x,y,z) # 1 2 3 #猜测游戏: 猜测用户输入的字符是否是9527 number=9527 guess=('请输入猜测数字') print(guess) print(type(guess)) # str #把字符串类型转为整型 guess=int(guess) print(type(guess)) # int if guess==number: print('猜对了!') elif guess<number: print('猜小了!') else: print('猜大了!') ''' while循环: 语法: while 判断条件: # 若条件成立则"循环"执行以下代码 print('111') break:结束本层循环 ''' import time while True: print(11111) time.sleep(1) break # 猜字符游戏:猜测用户输入的字符是否是9527,限制只能猜3次 number = 9527 init = 1 # 1 2 3 4 while True: # 若int大于3结束循环 if init > 3: print('猜错3次了,gun吧!') break guess= input('请输入猜测数字:') guess = int(guess) if guess == number: print('猜对了!') break elif guess < number: print('猜小了!') else: print('猜大了!') # 若没有退出循环证明猜错了,init + 1 init += 1 list1 = [1,2,3,4,5] # list1_len = len(list1) # 5 # #white list1_len > 0: # list1_len -= 1 # # print(list1_len) # 4 3 2 1 0 # print(list1{list1_len}) # 依次循坏取出list1中的每一个值 for x in list1: print(x) 笔记: 1.可变与不可变 当数据修改时,id不变称之为可变类型,否则称之为不可变类型。 2. - 流程控制 对流程的控制,控制某些事情的发生 -if分支判断: 语法: if判断条件: #条件若成立执行 print('条件成立') #若if条件成立,则执行此处 elif判断条件: print(另一个条件成立) #若if与elif条件不成立,则执行此处 else: # 若条件不成立则执行 print("条件不成立")