Map.prototype.setD = function(k,v){
	if (!this.has(k)){
		this.set(k,v)
		// clog("SetD")
		return 1
	}
		// clog("SetD0")
}

Set.prototype.isSuperset = function(subset) {
    for (var elem of subset) {
        if (!this.has(elem)) {
            return false;
        }
    }
    return true;
}

Set.prototype.union = function(setB) {
    var union = new Set(this);
    for (var elem of setB) {
        union.add(elem);
    }
    return union;
}

Set.prototype.intersection = function(setB) {
    var intersection = new Set();
    for (var elem of setB) {
        if (this.has(elem)) {
            intersection.add(elem);
        }
    }
    return intersection;
}

Set.prototype.difference = function(setB) {
    var difference = new Set(this);
    for (var elem of setB) {
        difference.delete(elem);
    }
    return difference;
}










Set.prototype.union_update = function(setB) {
    var union = this;
    for (var elem of setB) {
        union.add(elem);
    }
    return union;
}

Set.prototype.intersection_update = function(setB) {
    var intersection = this
    for (var elem of setB) {
        if (!this.has(elem)) {
            intersection.delete(elem);
        }
    }
    return intersection;
}

Set.prototype.difference_update = function(setB) {
    var difference = this;
    for (var elem of setB) {
        difference.delete(elem);
    }
    return difference;
}

/*
Set.prototype.symDifference = function(setB) {
    var difference = new Set(this.union(setB));
     var intersection = new Set(this.intersection(setB));
    for (var elem of intersection) {
        difference.delete(elem);
    }
    return difference;
}
*/

console.log("test")