小编use*_*127的帖子

请考虑以下代码:

   char foo[32] = "123456";
   printf("strlen(foo) = %d\n", strlen(foo));
   if ((5 - strlen(foo)) > 0)
   {
      //This statement prints because the comparison above returns true, why?
      printf("String must be less than 5 characters, test 1\n");
   }

   int tmp;
   if ((tmp = 5-strlen(foo)) > 0)
   {
      //This statement does not print and makes since
      printf("String must be less than 5 characters, test 2\n");
   }

正如评论所示,我不明白为什么在与另一个值工作进行比较之前需要一个临时变量来存储数学计算的结果.