package pl.edu.uwm.wmii.zyskadrian.laboratorium01;

import java.util.Scanner;


public class zadanie1i {
    private static int silnia(int i){
        if(i<1) return 1;
        else return i*silnia(i-1);
    }
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        System.out.print("Podaj liczbe calkowita: ");
        int n = in.nextInt();
        int suma = 0;
        for (int i = 1; i <= n; i++) {
            System.out.print("Podaj 1 rzeczywista: ");
            double x = in.nextDouble();
            if (i % 2 == 0) {
                suma = ((int) x)/silnia(i) + suma;
            } else {
                suma = suma - ((int)x)/silnia(i);
            }


        }
        System.out.println(suma);
    }}