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好同学们

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我们来看一下啊第三章的第32课

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循环控制语句哈

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我们呢总共呢是两个循环的控制语句

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另外呢课件上呢也给出了啊

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还有一个return哈

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这几个呢也都是可行的哈

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嗯第一个呢是死循环啊

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死循环的话呢就是在一直执行循环

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嗯你比如说我们来举个例子

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real 1I我们的条件是始终成立的

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sealt

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比如说啊还是我们的网站吧

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那么这样的话我们将会去一直执行

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一直在打印

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同学们可以看到哈

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啊因为我们是先判断条件

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如果为真的话我们就打印

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打印完之后呢再判断条件

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因为他这个条件始终为真

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所以呢他会一直打印

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那这是此循环哈

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那么我们

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呃如何从此循环当中跳出呢

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当然我们还有另外一种方法呢是for

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两个分号哈

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这两个呢是一样的

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啊一样的逻辑哈都是表示死循环哈

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那么

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我们如何从我们这个循环当中跳出呢

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哎你比如说

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呃同学们我们有这样一个小例题哈

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你比如说我现在有这个鸡蛋

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3个3个数剩两个

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4个4个数剩3个

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5个5个数剩4个

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呃 6个6个数剩

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剩5个 7个7个数剩两个

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比如说像这种题目

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啊那么问你鸡蛋最少有多少个呢

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哎我们就可以用一个死循环去做了

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我们不确定循环次数吗

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对吧

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我们来做一下看一下有没有答案啊

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啊如果M3等于等于2

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是不是余两个嘛

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并且M4等于等于3

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并且M5等于等于4

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并且M O 6等于等于5

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并且啊如果找不到答案我们就再

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改一改哈

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如果同时满足这些条件的话

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我们输出这个i

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输出完i以后呢

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我们开可以加一个break呢

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从这个死循环当中跳出

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因为我们这里呢是一直直行循环

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我们直到找到这个跳出的条件对吧

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我们可以看一下有没有呢

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有359同学们

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359的话就是这样一个鸡蛋的数量啊

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那么这里的话就可以用break呢

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来进行一个跳出

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那么break表示的是跳出当前循环啊

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跳出当前循环

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同学们可以看一下我们break语句

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在一个循环内时

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循环会立即终止

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且程序

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将流向紧跟着循环的下一条语句

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就执行到这个位置

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你比如说y循环的话

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brick的话会跳出当前循环啊

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而这个度l循环里面的话

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会也会跳出当前循环

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for for语句的话也会跳出当前循环啊

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接着去执行下一个语句

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所以呢我们如果说出现循环欠套的话

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啊那这时候的话我们要小心

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我们只能跳出一个循环啊

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它可以用于中中指对break呢

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还可以在我们switch case当中呢

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啊这个我们在第二章的时候学过哈

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啊

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这个的话啊还可以跳出中指switch啊

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语句当中的一个case

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如果你使用的是循环嵌套啊

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不瑞克语句

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会停止执行

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当前循环啊

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而不一定是最内层啊

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然后并且执行下一行代码啊

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这是我们的不瑞克语句

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那么我们再来看一下我们的continue语

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句continue语句的话呢是

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啊比如说啊

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同学们看这这个图画的也行啊

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Ctrl语句呢跟break类似哈

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但他不是强迫跳出循环啊

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而是跳过后面的语句哈

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你比如说我们的在这遇到一个Ctrl

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我们这个Ctrl后面的语句将不再直径

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而是直接回到我们的条件判断上去

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那么这是我们的度外

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我们for循环的话

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也是我们后面的语句呢将不再执行哈

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这是我们的Ctrl

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我们来看一下举个Ctrl循环的例子吧

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你比如说我们求基数的和

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给你一个n

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求技术盒

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那么我们

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if i摩2等于等于0的话continue

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i对吧如果它是偶数的话

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我们不去执行后面的语句啊

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否则的话i

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我们去执行这个sum加等于i

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最后输出sum

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当然我们这个语句的话

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就是刚刚这道题目

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并不一定非得用我们的Ctrl去做啊

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我们只是用这个呢来解释一下

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我们的Ctrl是不去忽略掉这个语句

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而而再回到我们的条件判断上来

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对吧那么接下来就是return了

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return的话表示是跳出函数

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那么这个题的话

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像是我们这道题

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我们不光可以用bree可跳出循环

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我们甚至呢可以直接return 0

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也是可行的啊

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啊你像我们这个题的话

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它是一个有有返回质的函数

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所以呢是return 0

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如果是个word无返回质的函数的话

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我们就return也就可以了哈

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结束函数

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好同学们

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那这就是我们的啊循环控制的语句

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那么我们去看一下我们的练习题