Constant and Macros in C

Constant and Macros in C

In this tutorial, We will learn about constant and macros in C programming language.

Constant in C

In C program we use the const keyword to define a constant variable.

 #include <stdio.h>   
 int main()   
 {   
   const int int_const_var = 10; // int constant   
   const float float_const_val = 4.14; // Real constant   
   const char char_const_val = 'A'; // char constant   
   printf("Integer constant :%d \n", intVal );   
   printf("Floating point constant : %f \n", floatVal );   
   printf("Character constant : %c \n", charVal );   
   return 0;   
 }   

Macros in C

A Macro is typically an abbreviated name given to a piece of code or a value. In C program we achieve this with help of keyword #define

 #include<stdio.h>   
 #define int_var 10   
 #define float_var 4.5   
 #define char_var 'A'   
 int main()   
 {   
   printf("Integer Constant: %d\n", int_var);   
   printf("Floating point Constant: %f\n", float_var);   
   printf("Character Constant: %c\n", char_var);   
   return 0;   
 }   

Please write comments if you find anything incorrect, or you want to share more information about the topic discussed above.