Pointer (selected from-sixth chapter--c Primer)

Uninitialized and illegal pointers:

For example: int *a;

*a=10;

There is no initialization when creating a pointer variable, so we are not sure where a will point, so we have no way of predicting where the 10 will be stored.

Therefore, you must be very careful before you make indirect access to pointers, and you need to ensure that they are initialized.

Null pointer

is a special pointer variable, which means that it does not point to anything, and to make a pointer variable null it can be assigned a value of 0.

It is illegal to dereference a null pointer because he does not point to anything.

Pointer (selected from-sixth chapter--c Primer)