example of source file

Example Source File in C with Explanations

Here is an example of a source file written in the C programming language, along with explanations for each step:

#include <stdio.h>

int main() {
   int num1, num2, sum;

   printf("Enter two numbers: ");
   scanf("%d %d", &num1, &num2);

   sum = num1 + num2;

   printf("The sum is: %d\n", sum);

   return 0;
}

Explanation:

  • The code begins with the #include <stdio.h> directive, which includes the standard input/output library in the program. This library provides functions like printf and scanf for input and output operations.
  • The main function is the entry point of the program. It has a return type of int and takes no arguments.
  • Inside the main function, three variables are declared: num1, num2, and sum. These variables are of type int and will be used to store user input and the sum of the two numbers.
  • The printf function is used to display a prompt message asking the user to enter two numbers.
  • The scanf function is used to read two integers from the user and store them in the variables num1 and num2.
  • The sum variable is assigned the sum of num1 and num2 using the + operator.
  • The printf function is used again to display the sum to the user.
  • Finally, the return 0 statement indicates the successful execution of the program.

This example demonstrates a simple C program that takes two numbers as input from the user, calculates their sum, and displays the result.