Understanding a simple addition program using C.

Program: Add Two Numbers

#include <stdio.h>

int main() {
    int num1 = 5;
    int num2 = 7;
    int sum;

    sum = num1 + num2;

    printf("The sum of %d and %d is: %d", num1, num2, sum);

    return 0;
}

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Explanation of Each Part

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1. #include <stdio.h>

• This line includes stdio header file.
• This line tells the computer:
  “I want to use printing functions like printf.”

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2. int main() {

• This is where the program starts running.

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3. int num1 = 5;

• This makes a number box called num1.
• We put the number 5 into that box.

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4. int num2 = 7;

• This makes another number box called num2.
• We put the number 7 into it.

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5. int sum;

• This is a third box, called sum.
• We will use it to store the result.

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6. sum = num1 + num2;

• We add the first and second numbers.
• Then we put the answer into the sum box.

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7. printf("The sum of %d and %d is: %d", num1, num2, sum);

• This prints the numbers and the answer.
• %d means “print a number.”

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8. return 0;

• This tells the computer:
  “The program finished without problems.”

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Final Output

When you run the program, it shows:

The sum of 5 and 7 is: 12