Essential C# If-Else Questions and Answers for HNDIT Students

Questions

1. Write a program that asks the user to enter a number and checks whether the number is even or odd.

2. Write a program that checks whether a given number is positive, negative, or zero.

3. Write a program that checks if the entered age qualifies a person as an adult (18 or older).

4. Write a program that checks if a student has passed or failed based on their score (passing score is 50).

5. Write a program that takes two numbers as input and prints the greater number.

6. Write a program that assigns a grade based on the score a user enters. Use the following conditions: Score >= 90: Grade A Score >= 80: Grade B Score >= 70: Grade C Score >= 60: Grade D Score < 60: Fail

7. Write a program that takes an integer between 1 and 7 and prints the corresponding day of the week.

8. Write a program that classifies the temperature into categories: Temperature >= 30: Hot Temperature >= 20: Warm Temperature >= 10: Cool Temperature < 10: Cold

9. Write a program that takes a BMI value as input and classifies it based on the following: BMI >= 30: Obesity BMI >= 25: Overweight BMI >= 18.5: Normal weight BMI < 18.5: Underweight

Answers

1. Check if the number is even or odd:

using System;

class Program {
    static void Main() {
        Console.Write("Enter a number: ");
        int number = int.Parse(Console.ReadLine());

        if (number % 2 == 0) {
            Console.WriteLine("The number is even.");
        } else {
            Console.WriteLine("The number is odd.");
        }
    }
}

2. Check if a number is positive, negative, or zero:

using System;

class Program {
    static void Main() {
        Console.Write("Enter a number: ");
        int number = int.Parse(Console.ReadLine());

        if (number > 0) {
            Console.WriteLine("The number is positive.");
        } else if (number < 0) {
            Console.WriteLine("The number is negative.");
        } else {
            Console.WriteLine("The number is zero.");
        }
    }
}

3. Check if the age qualifies as an adult:

using System;

class Program {
    static void Main() {
        Console.Write("Enter your age: ");
        int age = int.Parse(Console.ReadLine());

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

4. Check if a student has passed or failed:

using System;

class Program {
    static void Main() {
        Console.Write("Enter the score: ");
        int score = int.Parse(Console.ReadLine());

        if (score >= 50) {
            Console.WriteLine("You have passed.");
        } else {
            Console.WriteLine("You have failed.");
        }
    }
}

5. Print the greater of two numbers:

using System;

class Program {
    static void Main() {
        Console.Write("Enter the first number: ");
        int num1 = int.Parse(Console.ReadLine());

        Console.Write("Enter the second number: ");
        int num2 = int.Parse(Console.ReadLine());

        if (num1 > num2) {
            Console.WriteLine("The greater number is: " + num1); 
        } else {
            Console.WriteLine("The greater number is: " + num2); 
        }
    }
}

6. Assign a grade based on the score:

using System;

class Program {
    static void Main() {
        Console.Write("Enter the score: ");
        int score = int.Parse(Console.ReadLine());

        if (score >= 90) {
            Console.WriteLine("Grade A");
        } else if (score >= 80) {
            Console.WriteLine("Grade B");
        } else if (score >= 70) {
            Console.WriteLine("Grade C");
        } else if (score >= 60) {
            Console.WriteLine("Grade D");
        } else {
            Console.WriteLine("Fail");
        }
    }
}

7. Print the corresponding day of the week:

using System;

class Program {
    static void Main() {
        Console.Write("Enter a number (1-7): ");
        int day = int.Parse(Console.ReadLine());

        if (day == 1) {
            Console.WriteLine("Monday");
        } else if (day == 2) {
            Console.WriteLine("Tuesday");
        } else if (day == 3) {
            Console.WriteLine("Wednesday");
        } else if (day == 4) {
            Console.WriteLine("Thursday");
        } else if (day == 5) {
            Console.WriteLine("Friday");
        } else if (day == 6) {
            Console.WriteLine("Saturday");
        } else if (day == 7) {
            Console.WriteLine("Sunday");
        } else {
            Console.WriteLine("Invalid number. Please enter a number between 1 and 7.");
        }
    }
}

8. Classify temperature:

using System;

class Program {
    static void Main() {
        Console.Write("Enter the temperature: ");
        int temp = int.Parse(Console.ReadLine());

        if (temp >= 30) {
            Console.WriteLine("Hot");
        } else if (temp >= 20) {
            Console.WriteLine("Warm");
        } else if (temp >= 10) {
            Console.WriteLine("Cool");
        } else {
            Console.WriteLine("Cold");
        }
    }
}

9. Classify BMI:

using System;

class Program {
    static void Main() {
        Console.Write("Enter the BMI value: ");
        double bmi = double.Parse(Console.ReadLine());

        if (bmi >= 30) {
            Console.WriteLine("Obesity");
        } else if (bmi >= 25) {
            Console.WriteLine("Overweight");
        } else if (bmi >= 18.5) {
            Console.WriteLine("Normal weight");
        } else {
            Console.WriteLine("Underweight");
        }
    }
}

break;