c=a+++b 运算是什么意思？
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What does the operation c=a+++b mean?
提问by user595985
The following code has me confused
以下代码让我感到困惑
int a=2,b=5,c;
c=a+++b;
printf("%d,%d,%d",a,b,c);
I expected the output to be 3,5,8, mainly because a++ means 2 +1 which equals 3, and 3 + 5 equals 8, so I expected 3,5,8. It turns out that the result is 3,5,7. Can someone explain why this is the case?
我预计输出为 3,5,8，主要是因为 a++ 表示 2 +1 等于 3，而 3 + 5 等于 8，所以我预计为 3,5,8。结果是3,5,7。有人可以解释为什么会这样吗？
回答by Fred Foo
It's parsed as c = a++ + b, and a++means post-increment, i.e. increment after taking the value of ato compute a + b == 2 + 5.
它被解析为c = a++ + b,a++表示后增量，即取值a计算后的增量a + b == 2 + 5。
Please, neverwrite code like this.
请不要写这样的代码。
回答by Nawaz
Maximal Munch Ruleapplies to such expression, according to which, the expression is parsed as:
最大蒙克规则适用于该表达式，根据该规则，该表达式被解析为：
c = a++ + b;
That is, ais post-incremented (a++) and so the current value of a(before post-increment) is taken for +operation with b.
也就是说，a是后递增 ( a++) ，因此a（后递增之前）的当前值用于+与的运算b。
回答by David
a++ is postincrementing, i.e. the expression takes the value of a and thenadds 1.
c = ++a + b would do what you expect.
a++ 是后递增，即表达式取 a 的值然后加1。
c = ++a + b 会做你期望的。
回答by Stefano
This is an example of bad programming style.
这是一个糟糕的编程风格的例子。
It is quite unreadable, however it post increments aso it sums the current value of ato band afterwards increments a!
这是非常不可读的，但是它发布了增量，a因此它将ato的当前值b和之后的增量相加a！
回答by Patrick87
The post increment operator, a++, changes tge value of a after the value of a is evaluated in the expression. Since the original value of a is 2, that's what's used to compute c; the value of a is changed to reflect the new value after the ++ is evaluated.
后增量运算符 a++ 在表达式中计算 a 的值后更改 a 的 tge 值。由于 a 的原始值是 2，这就是用于计算 c 的值；在计算 ++ 后， a 的值会更改以反映新值。
回答by Aman Agarwal
a++ + b ..it gives the result 7 and after the expression value of a is update to 3 because of the post increment operator
a++ + b ..它给出了结果 7 并且在 a 的表达式值更新为 3 之后，因为后增量运算符
回答by jrok
a++ gets evaluated after the expression.
a++ 在表达式之后求值。
c = ++a + b; would give you what you thought.
c = ++a + b; 会给你你的想法。
回答by Vineet G
According to Longest Matchrule it is parsed as a++ + +b during lexical analysis phase of compiler. Hence the resultant output.
根据最长匹配规则，它在编译器的词法分析阶段被解析为 a++ + +b。因此产生的输出。
回答by Alok Negi
Here c= a+++b; means c= (a++) +b; i.e post increment. In a++, changes will occur in the next step in which it is printing a, b and c. In ++a, i.e prefix-increment the changes will occur in the same step and it will give an output of 8.
这里 c= a+++b; 表示 c= (a++) +b；即岗位增量。在 a++ 中，更改将在打印 a、b 和 c 的下一步中发生。在 ++a 中，即前缀递增，更改将发生在同一步骤中，并且输出为 8。
