Constant in C

It is an identifier whose value can not be changed at the execution time of program. In general constant can be used to represent as fixed values in a C program. Constants are classified into following types.

If any single character (alphabet or numeric or special symbol) is enclosed between single cotes ' ' known as single character constant.

If set of characters are enclosed between double cotes " " known as string character constant.

Declare constant

const keyword are used for declare a constant.

const int height = 100;

#include<stdio.h>
#include<conio.h>

void main()
{
const int a=10;
printf("%d",a);
a=20; // gives error you can't modify const
getch();
}