function calc( volume, weight, koeffFrom, koeffTo )
{
    var itg_ves=0;
    
    obm_ves=volume * 167;
    k = koeffFrom * koeffTo;
    
    if ( weight > obm_ves ) itg_ves = weight;
    else itg_ves = obm_ves;

    if (itg_ves < 50)   total = 50 * koef[0] * k;
    if (itg_ves >= 1600) total = -1;
    if (itg_ves >= 50  && itg_ves < 100)  total = itg_ves * koef[0] * k;
    if (itg_ves >= 100 && itg_ves < 200)  total = itg_ves * koef[1] * k;
    if (itg_ves >= 200 && itg_ves < 400)  total = itg_ves * koef[2] * k;
    if (itg_ves >= 400 && itg_ves < 800)  total = itg_ves * koef[3] * k;
    if (itg_ves >= 800 && itg_ves < 1600) total = itg_ves * koef[4] * k;

    return Math.round(total);
}
function keyfilter()
{
    var k = event.keyCode;
    if ( k == 0 || k == 10 || k == 13 || k == 44 || k == 46 )  return true;
    if ( k >= 48 && k <= 57 )  return true;
    return false;
}
function keyfilter2()
{
    var k = event.keyCode;
    if ( k == 0 || k == 10 || k == 13 )  return true;
    if ( k >= 48 && k <= 57 )  return true;
    return false;
}