import java.io.*; public class SumatoriaEsp { public static boolean primo(int num) { int cont = 0; for(int i =1; i < num; i++) { if (num % i == 0) { cont++; } } if (cont < 2) { return true; } else { return false; } } public static boolean multiploEspecial(int num) { boolean aux = false; if (num % 5 == 0 || num % 7 == 0) { aux = !aux; } return aux; } /* un metodo puede ser llamado desde otro método */ public static int sumatoria(int a, int b) { int sum = 0; for(int i = a; i <= b; i++) { if ( primo(i) ) { sum += i*i; } if ( multiploEspecial(i) ) { sum -= i;} /* System.out.println("i : " + i + " sum : " + sum); */ } return sum; } public static void main(String[] args) throws IOException { int a , b , s = 0; BufferedReader in = new BufferedReader(new InputStreamReader(System.in)); System.out.print("a : "); a = Integer.parseInt(in.readLine()); System.out.print("b : "); b = Integer.parseInt(in.readLine()); s = sumatoria(a,b); System.out.print("\n\nEl valor de la sumatoria de " + a + " hasta " + b + " es : " + s ); } }