指针常量和常量指针

using namespace std;

int main(){
    int a = 1;
    int b = 5;
    int c = 10;
    int *const p1 = &a;
    const int *p2 = &a;
    cout<<&a<<endl;
    cout<<&b<<endl;
    cout<<&c<<endl;
    cout<<p1<<endl;
    cout<<*p1<<endl;
    cout<<p2<<endl;
    cout<<*p2<<endl;
    *p1 = 2;//指针常量，指针不能修改，但是指针指向的值可以修改
    //p1 = &b;//报错，显示左值不能修改,即这个指针不能修改
    cout<<"---------------------"<<endl;
    cout<<p1<<endl;
    cout<<*p1<<endl;
    cout<<a<<endl;
    p2 = &c;//常量指针，指针可以修改，即这里原先指针指向的是a的地址，后来修改为c的地址
    //*p2 = 9;//报错，指针指向的内容不能修改
    cout<<"---------------------"<<endl;
    cout<<p2<<endl;
    cout<<*p2<<endl;
}

结果：
0x7ffeea3606bc
0x7ffeea3606b8
0x7ffeea3606b4
0x7ffeea3606bc
1
0x7ffeea3606bc
1
---------------------
0x7ffeea3606bc
2
2
---------------------
0x7ffeea3606b4
10