/// *******In the name of Allah*******;

const prompt = require("prompt-sync")();

var test = parseInt(prompt());

var T = 0;
while(test--)
{
    var n,m;
    T++;
    n = parseInt(prompt());
    m = parseInt(prompt());
    var sum = 0;
    for(var i=1;i<=n;i++)
    {
        var a;
        a = parseInt(prompt());
        sum += a;
    }
    console.log("Case #" + T + ": " + (sum%m) + "\n");
}