2018/09/04循环+运算

一:while循环

定义: 只要条件成立,就一直循环执行循环代码

机构:

while 条件:

　　循环执行代码

else:

　　执行代码2

例如:

while True:

　　print('0-0')

该函数则无限循环打印'0-0',直至天荒地老!

指令:break(推出本层循环)

       continue(推出本次循环)

二格式化输出

占位符:%  ( %d,占位指定取数值,%s: 占位指定取字符串,%r :  占位还原取值函数)

三 运算

python里面包含数学运算(如= - * / ),逻辑运算(and,or,not) 比较运算( ==   ,  <=  ,<= 等)

        and 并且。 左右两端同时为真。 结果才能是真
        or  或者。 左右两端有一个是真。 结果就是真
        not 非真即假， 非假即真

x or y  -> ( 如果x为0,取y,否则取x)

x and y   (如果x为0,则取X,否则取y)

运算顺序:  () > not > and > or

编码:

最早的计算机编码:ASCII 占8位

中国:
GBK : 占16位

最早的万国码:  unicode  占 32位

UTF-8: 可变长万国码,占位最短8位

UTF-16: 可变长万国码,占位最短16位

UTF-32: 可变长万国码,占位最短32位

print(1>1 or 3<4 or 4>5 and 2>1 and 9>8 or 7<6)  #True 
 print(not 2 > 1 and 3 < 4 or 4 > 5 and 2 > 1 and 9 > 8 or 7 < 6 )  #false 
 print(8 or 3 and 4 or 2 and 0 or 9 and 7 ) #8
 print(0 or 2 and 3 and 4 or 6 and 0 or 3 )  #4
 print(6 or 2 > 1)  #6 
print(3 or 2 > 1)  #3 
print(0 or 5 < 4 )  # False
 print(5<4 or 3) #3
 print(2>1 or 6) # true
 print(3 and 2>1) # 3 
print(0 and 3>1) # 0
 print(2>1 and 3) # 3 
print(3>1 and 0) # 0 
print(3>1 and 2 or 2<3 and 3 and 4 or 3>2) #2  
while 条件:    
　　 执行代码1 
else:    
　　 执行代码2

guess_num = int(input('请猜测幸运数字:')) 
while guess_num != 66: 
    if guess_num > 66: 
        print('猜大了!') 
　　　　guess_num = int(input('请猜测幸运数字:'))   
　　elif guess_num < 66:
    　　print('猜小了!') 
　　　　guess_num = int(input('请猜测幸运数字:')) 
else:   
  print('You are right !') 
guess_num = int(input('请输入正确的数字:')) 
count = 1 
while guess_num != 66:   
　　if count ==3: 
    　　print('Your are stupid !')    
    　　break 
    elif guess_num > 66:   
      　print('猜大了!')   
　　elif guess_num <66: 
    　　print('猜小了!')  
    elif guess_num == 66:    
     　　break       
　　　　print('Your are right!')   
　　　　count += 1    
 　　guess_num = int(input('请输入正确的数字:')) 
else:       
print('You are right !')
num = 1 
while num <= 10:  
 　　if num != 7:    
     　　print(num)   
  　num = num + 1 
count = 1
while count <10:   
  count += 1    
 　if count == 7:    
     continue    
 print(count)

 sum = 0 count = 1
 while count <= 100:    
      sum += count      
      count +=1 
      print(sum) 
count = 1
while count <=50: 
    print(count * 2 -1) 
    count +=1 
count = 1 
while count <= 50: 
    print(count * 2)  
  　count += 1  
count = 1 sum = 0 
while count < 50:
     a = count*2-1  
     b = a -count*2 
     sum = count * b + 99  
     count += 1 print(sum)
password = input('请输入您的密码:') 
count = 1
while count < 3:  
   times = 3 - count    
   print("密码错误,剩余 %d 次机会" % (times))   
   password = input('请输入您的密码:')     
   count = count + 1    
content = input('请输入广告词儿:') 
while "最" in content or "第⼀" in content or "稀缺" in content or "国家级" in content in content: 
    print("您的广告词非法!")   
    content = input('请输入广告词儿:') 
else:    
     print('合法')