using System;

using System.Linq;

var shards1 = Enumerable.Range(1, 3).Select(x => x.ToString()).ToArray();

var shards2 = Enumerable.Range(1, 4).Select(x => x.ToString()).ToArray();

​

int Randevue(string id, string[] shardNums)

{

    return shardNums.Select(x => (id + x).GetHashCode() % shardNums.Length).Max();

}

​

var diff = 0;

​

for (int i = 1; i < 100; i++)

{

    var r1 = Randevue(i.ToString(), shards1);

    var r2 = Randevue(i.ToString(), shards2);

    if (r1 != r2)

    {

        diff++;

    }

    Console.WriteLine($"{r1}, {r2}");

}

​

Console.Write($"diff:{diff}");