📝 Theory (Details)

• If Statement: Runs code only if a condition is true.

  if (age >= 18)
  {
      Console.WriteLine("You are an adult.");
  }
  else
  {
      Console.WriteLine("You are not an adult.");
  }
  

• Comparison Operators:

  • == equal

  • != not equal

  • > greater than

  • < less than

  • >= greater or equal

  • <= less or equal

• Logical Operators:

  • && (AND)

  • || (OR)

  • ! (NOT)

• Switch Statement: Cleaner way for multiple options.

  switch (dayOfWeek)
  {
      case 1: Console.WriteLine("Monday"); break;
      case 2: Console.WriteLine("Tuesday"); break;
      default: Console.WriteLine("Other day"); break;
  }
  

💻 Practice

Step 1 – Simple If/Else

Console.Write("Enter your age: ");
int age = Convert.ToInt32(Console.ReadLine());

if (age >= 18)
{
    Console.WriteLine("You are an adult.");
}
else
{
    Console.WriteLine("You are not an adult.");
}

Step 2 – If/Else If Chain

Console.Write("Enter your score (0–100): ");
int score = Convert.ToInt32(Console.ReadLine());

if (score >= 90)
    Console.WriteLine("Grade: A");
else if (score >= 75)
    Console.WriteLine("Grade: B");
else if (score >= 50)
    Console.WriteLine("Grade: C");
else
    Console.WriteLine("Grade: F");

Step 3 – Switch Example

Console.Write("Enter a number 1–3: ");
int option = Convert.ToInt32(Console.ReadLine());

switch (option)
{
    case 1: Console.WriteLine("Option One Selected"); break;
    case 2: Console.WriteLine("Option Two Selected"); break;
    case 3: Console.WriteLine("Option Three Selected"); break;
    default: Console.WriteLine("Invalid Option"); break;
}

Step 4 – Mini Exercise 🎯

Write a program that asks the user to enter a number.

• If divisible by 3 → print "Fizz"

• If divisible by 5 → print "Buzz"

• If divisible by both 3 and 5 → print "FizzBuzz"

• Otherwise print the number itself.