I just want to remind you, if I wanted to, for example, type in an expression like that, notice the syntactical form, it's an expression, a number, followed by an operand, followed by another expression.

我想要提醒下大家，如果你想要，例如，输入一个这样的表达式，注意语法形式，这是个表达式，一个数字，后面是一个运算对象，后面是另外一个表达式。

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But notice unlike a for loop, if you want to declare a variable or increment or decrement to variable, you've got to do that yourself.

但请注意不像for循环，如果你想声明一个变量,或者变大或变小一个变量，你需要自己完成。

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