Preprocessor Directives

 Preprocessor Directives

Preprocessor directives are special instructions to the compiler that are executed before the actual compilation process. They are used to perform various tasks like including header files, defining constants, conditional compilation, and more.

#include <stdio.h>

#define MAX(x, y) ((x) > (y) ? (x) : (y))

#ifdef DEBUG

#define DEBUG_PRINT(x) printf("Debug: %s\n", x)

#else

#define DEBUG_PRINT(x)

#endif

int main() {

    int a = 10;

    int b = 20;

    int max = MAX(a, b);

    printf("Maximum value: %d\n", max);

    DEBUG_PRINT("This is a debug message");

    return 0;

}