/* * Printing proper factors and counting prime numbers * Suggested exercises: * - Print the sum of the proper factors * - For each number print if it is deficient, abundant or perfect. * - Count how many numbers are deficient, abundant and perfect. */ public class Factors { public static void main (String[] args) { int n, f, fcount, p; p = 0; for (n = 1; n<=20; n++) { System.out.print(n + "\t"); fcount = 0; for (f = 1; f <= n/2; f++) if (n % f == 0) { System.out.print(f + " "); fcount++; } if (fcount == 1) p++; System.out.println(); } System.out.println("Number of primes = " + p); } }