using System.Collections.Generic;
using System.Linq;
public class Kata
{
    /// <summary>
    /// Checks if two char arrays contain at least one common item.
    /// </summary>
    /// <param name="a">First char array</param>
    /// <param name="b">Second char array</param>
    /// <returns>True if the arrays have at least one common item, false otherwise</returns>
    public static bool ContainsCommonItem(char[] a, char[] b)
    {
        // If all input arrays are valid and a intersect b, return true
        return a != null && b != null && a.Intersect(b).Any();
    }
}