sink.writeUtf8(String.format(" * %s = %s\n", i, factor(i)));
          }
          sink.close();
        } catch (IOException | InterruptedException e) {
          e.printStackTrace();
        }
      }

      private String factor(int n) {
        for (int i = 2; i < n; i++) {
          int x = n / i;
          if (x * i == n) return factor(x) + " × " + i;
        }
        return Integer.toString(n);