public int isPure() {
		if(timesPositive > 0 && timesNegative > 0) return 0;
		//catch the situation where both timesPositive and timesNegative are 0
		else if(timesPositive == 0 && timesNegative == 0) return 1;
		else return timesPositive - timesNegative;
		
	}