publicintpollDecrementHigherKey(intx){intsavedKey,savedValue;if(this.higherKey(x)==null){returnnull;//COMPILE-TIMEERROR}elseif(this.get(this.higherKey(x))>1){savedKey=this.higherKey(x);savedValue=this.get(this.higherKey(x))-1;this.remove(savedKey);this.put(savedKey,savedValue);returnsavedKey;}el
