Solution: Maximum Sum Subarray of Size k

using System;
class Program
{
    /// <summary>
    /// Finds the maximum sum of a sub-array with a given window size.
    /// </summary>
    /// <param name="arr">Array of integers.</param>
    /// <param name="k">Window size of the sub-array.</param>
    /// <returns>The maximum sum of a sub-array with the specified window size.</returns>
    public static int MaxSubArrayOfSizeK(int[] arr, int k)
    {
        int maxSum = 0;
        int windowSum = 0;
        // Iterate through the array with a sliding window of size k
        for (int i = 0; i <= arr.Length - k; i++)
        {
            windowSum = 0;
            // Sum the elements in the current window
            for (int j = i; j < i + k; j++)
            {
                windowSum += arr[j];
            }
            // Update the maximum sum
            maxSum = Math.Max(maxSum, windowSum);
        }
        return maxSum;
    }
    // Driver code to test above method
    public static void Main()
    {
        // Test cases
        int[] array1 = { 2, 1, 5, 1, 3, 2 };
        int k1 = 3;
        Console.WriteLine("Maximum sum of a sub-array of size K: " + MaxSubArrayOfSizeK(array1, k1));
        int[] array2 = { 2, 3, 4, 1, 5 };
        int k2 = 2;
        Console.WriteLine("Maximum sum of a sub-array of size K: " + MaxSubArrayOfSizeK(array2, k2));
    }
}