Creating a C Program

Let’s create a simple C program step by step and explain each component.

Open a text editor: To create a C program, you can use any text editor that allows you to save files as plain text. Notepad, Notepad++, Sublime Text, and Visual Studio Code are all popular choices.
Write the code: Here’s an example of a simple C program that calculates the sum of two integers and prints the result:
```
#include <stdio.h>

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

   sum = num1 + num2;
   
   printf("The sum of %d and %d is %d", num1, num2, sum);
   
   return 0;
}
```
Let’s break down each line:
- #include <stdio.h>: This line includes the standard input/output library, which provides functions for printing to the console and reading user input.
- int main() {: This line defines the main function, which is the entry point of the program. The int before main indicates that the function returns an integer value.
- int num1, num2, sum;: This line declares three integer variables called num1, num2, and sum.
- printf("Enter two numbers: ");: This line uses the printf function to print the message “Enter two numbers: ” to the console.
- scanf("%d %d", &num1, &num2);: This line uses the scanf function to read two integers entered by the user and store them in the num1 and num2 variables.
- sum = num1 + num2;: This line calculates the sum of num1 and num2 and stores the result in the sum variable.
- printf("The sum of %d and %d is %d", num1, num2, sum);: This line uses the printf function to print the message “The sum of [num1] and [num2] is [sum]” to the console, where [num1], [num2], and [sum] are replaced with the values of the corresponding variables.
- return 0;: This line exits the main function and returns a value of 0 to the operating system, indicating that the program executed successfully.
Save the file: Save the file with a .c extension, such as sum.c.
Compile the program: To run the program, you need to compile it first. Open a terminal or command prompt, navigate to the directory where the file is saved, and type the following command:
```
gcc sum.c -o sum
```
This command compiles the sum.c file and creates an executable file called sum.
Run the program: To run the program, type the following command in the terminal:
```
./sum
```
This will execute the sum program and print the message “Enter two numbers: ” to the console. Enter two integers, and the program will calculate their sum and print the result to the console.

And that’s it! You have created and run your first C program.

Share on Facebook

Save