import javax.script.ScriptEngineManager;
import javax.script.ScriptEngine;

class limit    {
	public static String formula = "x";
	public static int tendencia = 0;

	public static void main (String[] args) {
        System.out.println(args.length);
		if(args.length == 2)	{
			System.out.println("A fórmula é: " + args[0]);
			formula = args[0];
			tendencia = Integer.parseInt(args[1]);
			double res = limit( tendencia );
			System.out.println(" O limite é : " + res );
		}else{
			System.out.println("Maneira correta de uso: java limit \"FORMULA\" TENDENCIA");
		}
	}
	public static double EvalFunction(String f, double x)	{
		try	{
			ScriptEngineManager mgr = new ScriptEngineManager();
			ScriptEngine engine = mgr.getEngineByName("JavaScript");     
			f = f.replace("x", Double.toString(x));
			return Double.parseDouble(engine.eval(f).toString());
		} catch (Exception e) {
			System.out.println(e.toString());
			return Double.NaN;
		}
	}

	public static double f (double x)
	{
		return EvalFunction(formula, x);
	}
	public static double poslimit( double a )	{
		int a_n = (int) Math.round(a * 1000);
		double minn = Integer.MAX_VALUE;
		for(int x=a_n+20;x>a_n;x--)	{
			minn = Math.min(minn, f(x/1000.0));
		}
		System.out.println("LimPos: " + minn );
		return minn;
	}
	public static double neglimit( double a )	{
		int a_n = (int) Math.round(a * 1000);
		double maxn = Integer.MIN_VALUE;
		for(int x=a_n-20;x<a_n;x++)	{
			maxn = Math.max(maxn, f(x/1000.0));
		}
		System.out.println("LimNeg: " + maxn );
		return maxn;
	}
	public static double limit( double a )		{
		double neg = Math.round(neglimit(a)*100)/100.0;
		double pos = Math.round(poslimit(a)*100)/100.0;
		return ( neg==pos ) ? neg : Double.NaN;
	}
}