const int n=5;
int a[n];

#include<iostream>
using namespace std;

int main(void)
{
    const int a=3;
    int *pa=&a;
    *pa=4;
    printf("%d\n",*pa);
    printf("%d\n",a);
    return 0;
}

编译结果:
e:\c++\acm\lianxi.cpp(7) : error C2440: 'initializing' : cannot convert from 'const int *' to 'int *'