42 program [42] seeking digital
Title: ?? = 809 * 800 * 9 * + ?? 1 + ??
Wherein two digits represented by ??, ?? 8 * result of two digits, 9 * ?? result of 3 bits. ?? representatives seeking double-digit, and the result of 809 * ??.
package cskaoyan; public class cskaoyan42 { @org.junit.Test public void number() { long a = 809; long b = 0; for (long i = 10; i < 100; i++) { b = a * i; if (b >= 1000 && b <= 9999 && 8 * i <= 99 && 9 * i >= 100) { System.out.println(b + " = 800 * " + i + " + 9 * " + i); } } } }