Constants

If the keyword `const' is added in a variable declaration, the variable will be treated as a constant. Now its value cannot be changed in the program. Consider the following:

const int number=10;

Here, we have declared the variable `number' with the keyword `const' and assigned it a value of 10. `number' is now a constant and it will always have the value 10. If we try to change the value with a statement like:

number=20;

the code will generate an error.

Also note that the value in the constant needs to be assigned when it needs to be declared:

const int number=10;

If we do it like a variable,

const int number;
number=10;

this will also result in error.