吸血鬼数字的实现（thinking in java练习题）

/** 吸血鬼数字是指位数为偶数的数字，可以由一对数字相乘而得，而这对数字 各包含乘积的一半位数的数字，其中从最初的数字中选取的数字可以任意排序。 以两个0结尾的数字是不允许的。 例如，下面数字都是吸血鬼数字： 1260 = 21 * 60 1827 = 21 * 87 2187 = 27 * 81 写一个程序，找出4位数的所有吸血鬼数字。**/public class Test_05{public static void main(String[] args){check();}public static void check(){for(int i = 1000; i < 10000; i++){if(i %100 == 0) continue;int o = i%10;//oneint t = i/10%10;//tenint h = i/100%10;//hundrodint th = i/1000;//thound//System.out.println("i = " + i + " = " + thound + hundrod + ten + one);if(i == (th * 10 + h) * (t * 10 + o)){System.out.println(i + " = " + th + h + " * " + t + o);}if(th != h && i == (h * 10 + th) * (t * 10 + o)){System.out.println(i + " = " + h + th + " * " + t + o);}if(o != t && i == (th * 10 + h) * (o * 10 + t)){System.out.println(i + " = " + th + h + " * " + o + t);}if(th != h && o != t && i == (h * 10 + th) * (o * 10 + t)){System.out.println(i + " = " + h + th + " * " + o + t);}if(t != h){if(i == (th * 10 + t) * (h * 10 + o)){System.out.println(i + " = " + th + t + " * " + h + o);}if(th != t && i == (t * 10 + th) * (h * 10 + o)){System.out.println(i + " = " + t + th + " * " + h + o);}if(o != h && i == (th * 10 + t) * (o * 10 + h)){System.out.println(i + " = " + th + t + " * " + o + h);}if(th != t && o != h && i == (t * 10 + th) * (o * 10 + h)){System.out.println(i + " = " + t + th + " * " + o + h);}}if(o != h){if(i == (th * 10 + o) * (h * 10 + t)){System.out.println(i + " = " + th + o + " * " + h + t);}if(th != o && i == (o * 10 + th) * (h * 10 + t)){System.out.println(i + " = " + o + th + " * " + h + t);}if(h != t && i == (th * 10 + o) * (t * 10 + h)){System.out.println(i + " = " + th + o + " * " + t + h);}if(th != o && h != t && i == (o * 10 + th) * (t * 10 + h)){System.out.println(i + " = " + o + th + " * " + t + h);}}}}}// 1234: 12 * 34 || 21 * 34 || 12 * 43 || 21 * 43// 1234: 13 * 24 || 31 * 24 || 13 * 42 || 31 * 42// 1234: 14 * 23 || 41 * 23 || 14 * 32 || 41 * 32