Java中的算术运算符（初学者问题）

问题描述：

我知道数组运算符具有优先权。然后是二元关节运算符*，/，％。然后+和 - 它们是低优先级。

I know that array operators have the precedence. Then the binary arthimetic operators * , / , % . Then + and - which they are low precedence.

但是我很困惑在这个例子中哪个将首先解析java。
如果我们有2个运算符具有相同的优先级，那么首先在java中使用哪个运算符？

But I'm confused which one will java solve first in this example. And if we have 2 operators have the same priority, what operator will be used first in java?

谢谢。

int x = y = -2 + 5 * 7 - 7 / 2 % 5;

如果有人能为我解决这个问题，请逐一向我解释。因为这总是让我对考试感到困惑。

If someone could solve this for me and explain to me part by part. Because this always confuses me in exams.

答

如果运算符具有相同的优先级，则从左到右对它们进行求值。

If operators have the same precedence then they are evaluated from left to right.

来自教程：

当同一优先级
的运算符出现在同一表达式中时，规则
必须治理首先评估。
除
赋值运算符之外的所有二元运算符从左到右计算
;赋值
运算符从右到左进行计算。

When operators of equal precedence appear in the same expression, a rule must govern which is evaluated first. All binary operators except for the assignment operators are evaluated from left to right; assignment operators are evaluated right to left.

在表达式中， 7/2％5 ， / 和％具有相同的优先级，因此从左到右 7/2 = 3 和 3％5 = 3 。

In the expression, 7 / 2 % 5, the / and % have the same precedence, so going left to right 7 / 2 = 3 and 3 % 5 = 3.

最高优先级为* /％。以下是您的示例细分：

The highest precedence is given to * / %. Here is the breakdown of your example:

  -2 + 5 * 7 - 7 / 2 % 5
= -2 + (5 * 7) - (7 / 2 % 5)
= -2 + 35 - (3 % 5)
= -2 + 35 - 3
= 30

Java中的算术运算符（初学者问题）

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