吸血鬼數字的實現(thinking in java練習題)
阿新 • • 發佈:2019-02-02
/** 吸血鬼數字是指位數為偶數的數字,可以由一對數字相乘而得,而這對數字 各包含乘積的一半位數的數字,其中從最初的數字中選取的數字可以任意排序。 以兩個0結尾的數字是不允許的。 例如,下面數字都是吸血鬼數字: 1260 = 21 * 60 1827 = 21 * 87 2187 = 27 * 81 寫一個程式,找出4位數的所有吸血鬼數字。 **/ 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; //one int t = i/10%10; //ten int h = i/100%10; //hundrod int 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