与后递增和逻辑运算符混淆? [英] Confusion with post increment and logical operator?

问题描述

    #include <stdio.h>
    #include <string.h>

    main()
    {
         int i=-1, j=-1, k=0, l=2,m;
         m = i++&&j++&&k++||l++;
         printf("%d%d%d%d%d", i, j, k, l, m);
    }

输出:

00131

00131

我很困惑表达式的求值方式.

I am confused how the expression is getting evaluated.

推荐答案

这里真正重要的是||.由于l++的计算结果为布尔值1(true)，因此整个语句为true.因此m为1，其余的只是它们的原始值加上一个值，这些值在求值后都会递增.

All that really matters here is the ||. Since l++ evaluates to the boolean 1 (true), the entire statement is true. So m is 1, and the rest are just their original values plus one for the post increment after they are evaluated.

您正在评估布尔表达式:

You're evaluating the boolean expression:

((-1 && -1) && 0) || 2

---

顺便说一句，您对main的定义应为:

---

As an aside, your definition of main should be:

int main(void)

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