#include<iostream>
class MyClass
{
public:
int i;
MyClass operator+=(int j)
{
i += j;
return *this;
}
MyClass operator+(const MyClass& b)
{
MyClass tmp;
tmp.i = this->i + b.i;
return tmp;
}
MyClass operator++()//前置++
{
return *this += 1;
}
MyClass operator++(int)//后置++
{
MyClass temp = *this;
*this += 1;
return temp;
}
};
int main()
{
int i = 2;
int result = i++ + i++ + i++;
std::cout << result << '\t' << i << std::endl;
i = 2;
result = ++i + ++i + ++i;
std::cout << result << '\t' << i << std::endl;
MyClass a;
a.i = 2;
MyClass result2 = a++ + a++ + a++;
std::cout << result2.i << '\t' << a.i << std::endl;
a.i = 2;
result2 = ++a + ++a + ++a;
std::cout << result2.i << '\t' << a.i << std::endl;
}
同样的代码,vs中的运行结果是
dev-c的运行结果是
其它的都好理解,我不明白的是
int i = 2;
int result = ++i + ++i + ++i;
在dev中的结果为什么是13?