private boolean containsPrefixHelper(String s, int indexLow, int indexMid, int indexHigh){
		if(LexiconArrayList.get(indexLow).startsWith(s) || LexiconArrayList.get(indexMid).startsWith(s) || LexiconArrayList.get(indexHigh).startsWith(s)){
			return true;
		}else if(s.compareTo(LexiconArrayList.get(indexLow)) < 0 || s.compareTo(LexiconArrayList.get(indexHigh)) > 0){
			return false;
		}else if(s.compareTo(LexiconArrayList.get(indexMid)) > 0 && s.compareTo(LexiconArrayList.get(indexHigh)) < 0){
			indexMid++;
			indexHigh--;
			return containsPrefixHelper(s, indexMid, ((indexMid+indexHigh)/2) ,indexHigh);
		}else if(s.compareTo(LexiconArrayList.get(indexMid)) < 0 && s.compareTo(LexiconArrayList.get(indexLow)) > 0){
			indexLow++;
			indexMid--;
			return containsPrefixHelper(s, indexLow, ((indexLow+indexMid)/2) ,indexMid);
		}
		return false;
	}