If you know you're not gonna output a full string %C but a single character, percent C will get that job done.

如果你不想输出一个完整的字符串,而是输出一个字母，就要用到。

哈佛公开课 - 计算机科学课程节选

The number that you choose to rotate your letters by is what we call in cryptography, a key.

你选择的旋转字母的数量,就是所谓的加密学，一个密钥。

哈佛公开课 - 计算机科学课程节选

And for those of you at the very end of the alphabet, 1-190 we have a special room for you, 1-190, so everybody has some elbow room.

而你在字母表的末尾，我们给准备了一个特别的房间，因此，每个人都有些活动空间。

麻省理工公开课 - 固态化学导论课程节选

I mean, you're into the ballgame for an alphabet such as ours.

我是说,你进入了一个字母表的游戏中,这种字母表与我们的类似

耶鲁公开课 - 古希腊历史简介课程节选

You rotate the letters by a deterministic amount, by a fixed number of steps so that the end result is actually something that can be reversed.

你用确定的数量旋转那些字母，通过一个固定数量的步骤,这样，最终结果是可以把它,反加密出来。

哈佛公开课 - 计算机科学课程节选

You have to come up with a convention that maps numbers to letters.

你必须提出一个,数字与字母对应的协定。

哈佛公开课 - 计算机科学课程节选

GetDouble If you just want a single letter from the user, GetDouble.

如果你想得到一个单独的字母，用。

哈佛公开课 - 计算机科学课程节选

So it does that for us so that you can get away with just knowing the address of the first byte and it will make sure that you know when to stop by including the special value so, in fact, get the string if you type in a three-letter word, we allocate four bytes no matter what because we need an additional byte 0 for this special sentinel value back slash zero at the very end.

它为我们做了这些事情，这样我们就可以,通过第一个字节的地址,它还可以通过包含一个特殊的值,来保证在哪里停止，如果你输入了一个三个字母的单词,就可以获得那个字符串，不管怎样，我们分配四个字节,因为我们在末端需要一个额外的字节,来保存这个特殊的标志值--反斜杠。

哈佛公开课 - 计算机科学课程节选

Now, once you know each of those, you can now do 25 more upper case letters and 25 more lower case letters then there are some other stuff like punctuation and things you see on the keyboard.

一旦你知道两者中的任何一个，你就知道了另外25个,大写字母和小写字母,标点和在键盘上的,各种符号也有ASCII码。

哈佛公开课 - 计算机科学课程节选

A If you want to convert a number like 65 to the letter A, you just have tell the computer "cast that int to a char."

如果你要把一个像65这样的数字转换为字母，你只需要告诉计算机“把那个int型数据转换成char型处理“

哈佛公开课 - 计算机科学课程节选

Well, turns out that with arrays, not to make this too trippy too soon, but Arg V bracket something is a string, you can also use square bracket notation to go to a specific letter in a string, because little teaser a string is just an array.

好的，结果用那个数组，不要使这个很快引起幻觉，但是Argv什么的，是一个字符串，你也可以用方括号定位到,字符串中的一个特定的字母，因为一个字符串只是一个数组。

哈佛公开课 - 计算机科学课程节选