分析：对等式变型可得y的范围在k到2k之间，暴力。
import java.util.ArrayList; import java.util.List; import java.util.Scanner; public class Main{ public static void main(String[] args) { Scanner scanner = new Scanner(System.in); while (scanner.hasNext()) { int k = scanner.nextInt(); List<String> list = new ArrayList<>(); for (int y = k + 1; y <= 2 * k; y++) { int dividend = k * y; int divisor = y - k; if (dividend % divisor == 0) { int x = dividend / divisor; String string = "1/" + k + " = " + "1/" + x + " + " + "1/" + y; list.add(string); } } System.out.println(list.size()); for (String string : list) { System.out.println(string); } } } }
