Greatest of three numbers C# Exercise - C# Programming Course

 Lesson

Flow Control

 Exercise

Greatest of three numbers

 Objetive

Write a C# program that prompts the user to enter three numbers and displays the greatest one.

 Example Code

using System; // Importing the System namespace to use Console functionalities

class Program
{
    // Main method where the program execution begins
    static void Main()
    {
        double firstNumber, secondNumber, thirdNumber; // Declaring variables to store the three numbers entered by the user

        // Asking the user to enter the first number and reading the input
        Console.Write("Enter the first number: ");
        firstNumber = Convert.ToDouble(Console.ReadLine()); // Converting the input to a double

        // Asking the user to enter the second number and reading the input
        Console.Write("Enter the second number: ");
        secondNumber = Convert.ToDouble(Console.ReadLine()); // Converting the input to a double

        // Asking the user to enter the third number and reading the input
        Console.Write("Enter the third number: ");
        thirdNumber = Convert.ToDouble(Console.ReadLine()); // Converting the input to a double

        // Checking which number is the greatest using if-else statements
        if (firstNumber >= secondNumber && firstNumber >= thirdNumber) // If the first number is greater than or equal to both other numbers
        {
            // Displaying the first number as the greatest
            Console.WriteLine("The greatest number is: {0}", firstNumber); // Printing the greatest number
        }
        else if (secondNumber >= firstNumber && secondNumber >= thirdNumber) // If the second number is greater than or equal to both other numbers
        {
            // Displaying the second number as the greatest
            Console.WriteLine("The greatest number is: {0}", secondNumber); // Printing the greatest number
        }
        else // If the third number is greater than or equal to both other numbers
        {
            // Displaying the third number as the greatest
            Console.WriteLine("The greatest number is: {0}", thirdNumber); // Printing the greatest number
        }
    }
}

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