static int leading_sacrifice_group()
{
    int weights[5];
    get_pure_deck_weights(weights);
    int best_i = -1, maxweight = -1;
    for ( int i = 0; i < 5; ++i )
    {
        if ( best_i == -1 || weights[i] > maxweight )
        {
            maxweight = weights[i];
            best_i = i;
        }
    }
    return best_i;
}
static void give_sac_group_feedback(int which)
{
    ASSERT( which >= 0 && which < 5 );
    const char* names[] = {
        "Escape", "Destruction", "Dungeons", "Summoning", "Wonder"
    };
    mprf(MSGCH_GOD, "A symbol of %s coalesces before you, then vanishes.",
         names[which]);
}

    const int old_leading = leading_sacrifice_group();

                std::string msg = "Really sacrifice ";
                msg += item.name(DESC_NOCAP_A);
                msg += "?";

                const std::string msg =
                    "Really sacrifice " + item.name(DESC_NOCAP_A) + "?";

            // Aproximate piety gain chance.
            // Value:  %
            // ---------
            //    10:  9.0%
            //    20: 17.5%
            //    30: 25.5%
            //    40: 34.0%
            //    50: 42.5%
            //    60: 50.0%
            //    70: 58.0%
            //    80: 63.0%

    if ( num_sacced > 0 && you.religion == GOD_NEMELEX_XOBEH )
    {
        const int new_leading = leading_sacrifice_group();
        if ( old_leading != new_leading || one_chance_in(50) )
            give_sac_group_feedback(new_leading);
    }