C#: Check a given array of integers and return true if the array contains 10 or 20 twice

Last update on June 27 2025 13:09:21 (UTC/GMT +8 hours)

Check if 10 or 20 Appears Twice in Array

Write a C# Sharp program to check a given array of integers and return true if it contains 10 or 20 twice. The array length will be 0, 1, or 2.

Visual Presentation:

Sample Solution:-

C# Sharp Code:

using System; // Importing the System namespace

namespace exercises // Defining a namespace called 'exercises'
{
    class Program // Defining a class named 'Program'
    {
        static void Main(string[] args) // The entry point of the program
        {
            // Output the result of the 'test' method with different integer arrays as arguments
            Console.WriteLine(test(new[] { 12, 20 })); // Calling test method with array [12, 20] and displaying the result
            Console.WriteLine(test(new[] { 20, 20 })); // Calling test method with array [20, 20] and displaying the result
            Console.WriteLine(test(new[] { 10, 10 })); // Calling test method with array [10, 10] and displaying the result
            Console.WriteLine(test(new[] { 10 })); // Calling test method with array [10] and displaying the result
        }

        // Method to check if the input array has a length of 2 and contains either two 10s or two 20s
        public static bool test(int[] nums)
        {
            // Checking if the array length is equal to 2
            // and if the elements are either both 10 or both 20
            return nums.Length == 2
&& ((nums[0] == 10 && nums[1] == 10)
                     || (nums[0] == 20 && nums[1] == 20));
        } 
    }
}

Sample Output:

False
True
True
False

Flowchart:

Go to:

• C# Sharp Basic Algorithm Exercises Home ↩
• C# Sharp Programming Exercises Home ↩

PREV : Double Length Array with First Element Copied.
NEXT : Set 7 to 1 if Followed by 5.

C# Sharp Code Editor:

Improve this sample solution and post your code through Disqus