At the end of the day, you can implement the exact same program using a while loop that you can using a for loop, it's just your code is going to look slightly different.

最终，你可以执行这个程序,再使用for循环的地方使用while循环，这只是使你的代码看起来稍微有点不同。

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You seem to be upset.

你看起来有点沮丧。

It seems 实战 - SpeakingMax英语口语达人

So conceptually the key difference here, besides the syntax looking slightly different, it just means that if you want a chunk of code to execute no matter what initially, ; you can use the do while loop; if you want to check a condition first, you can use the while loop.

所以概念上，则关键的区别是，除了语法看起来有点不同，它的意思是如果你想要一段代码,最初无论如何都要执行，你就可以用do，while循环;,如果你想要先检查条件，你可以用while循环。

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This might look a little cryptic at first, but it turns there is some very obvious patterns here, for instance. According to this chart, if you want to represent the letter A A in the so called ASCII system, what number do you actually use to do so?

起初，它看起来有点神秘，但你会发现它有一些明显的对应模式，这里就有例子，根据图表，在所谓的ASCII系统中,你想表示字母，你该用哪些数字呢？

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