var ktm_ID = new Array();

function DoCompare(siteweb) {
  var e;
    var err = [];

    if (ktm_ID.length != 2)  
	  err[err.length] = "Musisz zaznaczyć 2 produkty do porównania."; 
    
	if (err.length) {
      msg = '';
      for (e=0; e<err.length; e++) {
        n=e+1;
        msg += n + '. ' + err[e];
      }
      alert(msg);
    } else {
      url = "?do=productcompare&";
      for (i=0; i<ktm_ID.length;i++){
         url += "productKTM" + [i+1] + "=" + ktm_ID[i] + "&";
      }
      window.location = siteweb + url;;
    }
  }
  
  function toCompare(ktmID){
    ktm_ID[ktm_ID.length++] = ktmID;
  }

  function deleteCompare(ktmID){
    start = getIndex(ktmID, ktm_ID);
    ktm_ID.splice(start,1);
  }
  
    function getIndex(value, array){
    for(i=0;i<array.length;i++){
        if(array[i] == value) return i;
    }
    return -1;
  }