c++ - 在 C++ 中如何调用错误？

Question

我正在研究 Bjarne Stroustrup 的编程第 3 章:使用 C++ 的原理和实践

Prompt the user to enter the age or the recipient and assign it to an int variable age. Have your program write "I hear you just had a birthday and You are age years old." If age is 0 or less or 110 or more, call error("you're kidding!").

cout<<"Enter the age of "<<friend_name<< ".\n";
int age=0;
cin>>age;
if (age==0)
    cout<<"you're kidding!";

if (age>=110)
    cout<<"you're kidding!";

if (age!=0, 110)
    cout<<"I hear you just had a birthday and you are " <<age<< " years old.\n";

我尝试执行上面的代码，但它一直给我

"you're kidding! I hear you you just had a birthday and you are 0 years old"

但我认为那是不对的。我认为它应该做其中之一而不是两者，但我不知道如何让它做到这一点。

Answer 1

if (age!=0, 110) 是你的问题。逗号运算符返回最右边的表达式，因此该代码等效于 if(110)。