#include<iostream>
#include<ctime>
#include<iomanip>
using namespace std;
int main()
{
cout << ('9' - '3') << endl;
cout << sizeof('9' - '3');
}
运行结果为6 4
为什么
```
#include<iostream>
#include<ctime>
#include<iomanip>
using namespace std;
int main()
{
cout << ('9' - '3') << endl;
cout << sizeof('9' - '3');
}
运行结果为6 4
为什么
```