docs: public boolean removeKey(long key) {
  	int i = indexOfKey(key);
  	if (i<0) return false; // key not contained
  
  	this.state[i]=REMOVED;
  	this.values[i]=0; // delta
  	this.distinct--;
  
  	if (this.distinct < this.lowWaterMark) {
  		int newCapacity = chooseShrinkCapacity(this.distinct,this.minLoadFactor, this.maxLoadFactor);
  		rehash(newCapacity);
  	}
  	
  	return true;	
  }