C# Program to add two numbers

Program

using System;
namespace add_two_numbers
{
	class AddTwoNumbers
	{
		static void Main(String[] args)
		{
			int a, b;
			Console.Write("Enter first number:\t");
			a = int.Parse(Console.ReadLine());
			Console.Write("Enter second number:\t");
			b = int.Parse(Console.ReadLine());
			int sum = a + b;
			Console.WriteLine("Sum of two numbers: " + sum);
		}
	}
}

This C# program takes two integer inputs from the user, adds them, and prints the sum.

1. using System;

   • Imports the System namespace, which provides core functionalities, including console input/output.

2. namespace add_two_numbers

   • Defines a namespace called add_two_numbers to group related classes.

3. class AddTwoNumbers

   • Declares a class named AddTwoNumbers, which contains the program logic.

4. static void Main(String[] args)

   • The Main method is the entry point of the program.
   • static means it belongs to the class and does not require an instance.
   • void means the method does not return any value.
   • String[] args allows command-line arguments to be passed.

5. Declaring Variables:

   • int a, b; → Declares two integer variables.

6. Reading User Input:

   • Console.Write("Enter first number:\t");

     • Displays a message asking for input.

   • a = int.Parse(Console.ReadLine());

     • Reads user input as a string and converts it to an integer using int.Parse().

   • Similarly, the second number is read and stored in b.

7. Adding the Two Numbers:

   • int sum = a + b;
     • Calculates the sum of a and b and stores it in the variable sum.

8. Displaying the Result:

   • Console.WriteLine("Sum of two numbers: " + sum);
     • Prints the sum to the console.

Output

$ mcs AddTwoNumbers.cs 
$ mono AddTwoNumbers.exe
Enter first number:	34
Enter second number:	567
Sum of two numbers: 601