Following are some incomplete declarations, what do each of them mean?

1.	Following are some incomplete declarations, what do each of them mean?
Answer» 1. const int X;2. int const x;3. const int x;4. int const x;5. int const * x const; The first two declaration points 1 and 2 mean the same. It means that the variable x is a read-only constant integer. The third declaration represents that the variable a is a pointer to a constant integer. The integer value can't be modified but the pointer can be modified to POINT to other locations. The fourth declaration means that the variable x is a constant pointer to an integer value. It means that the integer value can be changed, but the pointer can't be MADE to point to ANYTHING else. The last declaration means that the variable x is a constant pointer to a constant integer which means that neither the pointer can point to a different location nor the integer value can be modified.

Answer»

1. const int X;2. int const x;3. const int *x;4. int * const x;5. int const * x const;

The first two declaration points 1 and 2 mean the same. It means that the variable x is a read-only constant integer.
The third declaration represents that the variable a is a pointer to a constant integer. The integer value can't be modified but the pointer can be modified to POINT to other locations.
The fourth declaration means that the variable x is a constant pointer to an integer value. It means that the integer value can be changed, but the pointer can't be MADE to point to ANYTHING else.
The last declaration means that the variable x is a constant pointer to a constant integer which means that neither the pointer can point to a different location nor the integer value can be modified.

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