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。

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FOR c It's going to say FOR c, which was my name for the character in that string.

那么循环要去做什么呢？循环要去说,也就是字符串中字符的名字。

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