const trick

1. const int* x=5;

Declares a pointer to a constant.
So now a assignment *x=10; will fail

2. int* const x=5;
Declares a constant pointer to a variable.
so *x=10 will PASS while x=10 will fail.

3. const int * == int const *
The above 2 mean the same thing

4. const int const *x=5;

Using 3. statement 4 Declares a pointer to a constant. (same as 1)