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 */
package metoda_simpsona;

import java.util.Scanner;

/**
 *
 * @author Student
 */
public class Metoda_Simpsona {


    public static double caleczka (double x)
    {
        return Math.sin(1.1*x-0.3)/(2.5 + Math.pow(x, 2));

    }
    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        // TODO code application logic here
        double a=0.4;
        double b=2.2;
        double wyn,h;
        int n ;

        Scanner el_wejsciowy =new Scanner(System.in);
        System.out.println("Podaj n");
        n=el_wejsciowy.nextInt();

         h=(b-a)/n;

        double [] x = new double[n+1];


        for (int i=0;i<x.length;i++)
        {
            x[i]= (a + (i*(b-a)/n));
        }
        double [] y = new double[n];
        for (int i=0;i<y.length;i++)
        {
            y[i]= (x[i] + x[i+1])/2;
        }

        wyn= 0;
        for(int i=0;i< x.length;i++)
        {
            if(i==(x.length-1))
            {
                wyn += caleczka(x[i]);
            }
            else {
                wyn += caleczka(x[i])*2;
            }
        }
        for (int i=0;i<y.length;i++)
        {
            wyn += caleczka(y[i])*4;
        }
        wyn *=(h/6);
        System.out.println("Calka wynosi:" + wyn);
    }

}