while 语句时还有另外两个重要的命令 continue,break 来跳过循环,continue 用于跳过该次循环,break 则是用于退出循环,此外"判断条件"还可以是个常值,表示循环必定成立,具体用法如下: # continue 和 break 用法i=1whilei<10:i+=1ifi%2>0:# 非双数时跳过输出continueprinti# 输出双数2、4、6、8、10i=1while...
即 while 循环正常结束,程序将进入到可选的 else 段。while...else 有点类似于 if...else,这里需...
whileTrue:ifcount ==3;break# 结束退出# 优化代码whilecount <3: 实例:打印100以内的偶数 count=0whilecount<=100: ifcount%2==0:# 除以2余数为0的数print("loop ",count)count+=1print("---end---") 实例:第50次不打印,第60-80打印对应值的平方 count=0whilecount<=100: ifcount==50: pass#...
Here, on the third iteration, thecounterbecomes2which terminates the loop. It then executes theelseblock and printsThis is inside else block. Note: Theelseblock will not execute if thewhileloop is terminated by abreakstatement. Python for loop vs while loop Thefor loopis usually used in the...
Python for loop and while loop #!pyton2#-*- coding:utf-8 -*-forletterin"Python":print"Current letter is:",letter fruits=["apple","mango","pear"]forfruitinfruits:printfruitforindexinrange(len(fruits)):printfruits[index]>python2 test.py...
python if-statement while-loop number = int(input("please choose your number: ")) while number > number_to_guess: number = int(input("Your guess is wrong it was bigger then the generated number, try again: ")) while number < number_to_guess : number = int(input("Your guess was ...
译自 How (and When) to Use a Python While Loop,作者 Jack Wallen。While 循环是编程的一个基本要素。While 循环所做的是继续执行一条语句(或一组语句),直到满足特定条件。一个显而易见的例子(许多人都会理解)可能是这样的:只要我的银行账户有钱,我就可以买东西。该语句是我可以买东西,条件是只要...
classBreakLoop(Exception):passtry:while条件1:while条件2:# 执行代码块if条件3:raiseBreakLoopexceptBreakLoop:pass 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 在上面的代码中,我们定义了一个名为BreakLoop的异常类,并在内层循环中使用raise语句抛出这个异常。然后,在外层循环中使用try-except语句捕获这个...
1. if 语句 ① 在Python中没有switch – case语句。② if 条件冒号后的语句,表示满足条件后要执行...
if inp_name == username and inp_pwd == password: print("登陆成功") else: print("输入的用户名或密码错误!") #通常认证失败的情况下,会要求用户重新输入用户名和密码进行验证,如果我们想给用户三次试错机会,本质就是将上述代码重复运行三遍,你总不会想着把代码复制3次吧。。。 username...