代码:
#include<iostream>
using namespace std;
int main()
{
unsigned long long a = 0x90 << 24;
cout << hex << a; // 输出: ffffffff90000000
}
#include<iostream>
using namespace std;
int main()
{
unsigned long long a = 0x90 << 24;
cout << hex << a; // 输出: ffffffff90000000
}