function filterTankstellen(tankstellen, kraftstoff){
    var preise = [];

    for(var i = 0; i < max; i++){
        $(tankstellen[i].prices).each(function() {
            if(this.type == kraftstoff) {
                console.log(tankstellen[i].id);
                var tanke = {tankstellen[i].id : this.price};
                preise.push({i : this.price,});
            };
        });
    };
};