const的用法

用一个实例代码来记录一下使用const定义的变量可以怎样赋值

#include <stdio.h>
int main()
{
    int b = 10;
    const int a = b;
    int const c = b;
    a = 10; //error, con't modify read-only.
    c = 11; //error, con't modify read-only.

    const int *e = &b;  //*e is const, but e is not read-only.
    int f = 20;
    *e=13; //error, con't modify read-only.
    e= &f; //ok.


    int * const g = &b; //g is const, but *g is not read-only.
    *g = 21;//ok
    g = &f; //error.

    return 0;
}