为什么结果不是65呢?
```c++
#include <iostream>
int main()
{
unsigned a{ 1000 };
int* ptr{};
ptr = (int*) &a;
*ptr = -1;
char* ctr{};
ctr = (char*)ptr;
*ctr = 'A';
std::cout << a;
system("pause");
return 0;
}
```