cbegin是指针
到恒定的东西
. 您可以将该指针更改为指向相同常量类型的对象。
你把它和指针混淆了,指针是常数,指向的是非常数。
const int* cp; // pointer to a constant value, but can point to something else
int* const pc; // pointer is constant, value can change
const int* const cpc; // pointer cannot be changed, value it points to cannot be changed
const int value = 5; // can never change value
const int value2 = 10; // can never change value
const int* cp = &value; // our pointer to const int points at a const int
*cp = 6; // error: the value of something const can't be changed
cp = &value2; // fine, because we're pointing at a const int
int* p const = &value; // error: trying to point a pointer to non-const to a const, which would allow us to:
*p = 7; // which should be illegal.
