using System;

internal static class Program
{
    private static void Main(string[] args)
    {
        int[] counts = { 3, 4, 5 };
        Console.WriteLine($"Total: {Total(counts)}");
        ReadOnlySpan<int> middle = counts.AsSpan(1, 1);
        Console.WriteLine($"Middle: {middle[0]}");
    }

    internal static int Total(ReadOnlySpan<int> values)
    {
        int total = 0;
        foreach (int value in values) total = checked(total + value);
        return total;
    }
}