指针常量与常量指针

#include <iostream>
using namespace std;

int main()
{
  int x = 1;
  int y = 2;

  //指针常量(指针的值不能修改，指向的内容可以修改)
  int * const p = &x; //const修饰p
  //p = &y; //误
  *p = 3;

  //常量指针(指向常量的指针，指针的值可以修改，指向的内容不能修改)
  const int * q = &x; //const修饰int
  //int const * q = &x; //同上
  q = &y;
  //*q = 3; //误



  int ttt = 0;

  return 0;
}