Poj 1316 Self Numbers(水题)

一、Description

In 1949 the Indian mathematician D.R. Kaprekar discovered a class of numbers called self-numbers. For any positive integer n, define d(n) to be n plus the sum of the digits of n. (The d stands for digitadition, a term coined by
Kaprekar.) For example, d(75) = 75 + 7 + 5 = 87. Given any positive integer n as a starting point, you can construct the infinite increasing sequence of integers n, d(n), d(d(n)), d(d(d(n))), .... For example, if you start with 33, the next number is 33 +
3 + 3 = 39, the next is 39 + 3 + 9 = 51, the next is 51 + 5 + 1 = 57, and so you generate the sequence




33, 39, 51, 57, 69, 84, 96, 111, 114, 120, 123, 129, 141, ...

The number n is called a generator of d(n). In the sequence above, 33 is a generator of 39, 39 is a generator of 51, 51 is a generator of 57, and so on. Some numbers have more than one generator: for example, 101 has two generators, 91 and 100. A number with
no generators is a self-number. There are thirteen self-numbers less than 100: 1, 3, 5, 7, 9, 20, 31, 42, 53, 64, 75, 86, and 97.

Input

No input for this problem.

Output

Write a program to output all positive self-numbers less than 10000 in increasing order, one per line.

二、题解

        只做学习记录！

三、Java代码

public class Main {

    public static void main(String[] args) { 

    	boolean flag[]=new boolean[10001];
    	int t;
    	for(int i=1;i<10000;i++){
    		t=i+i/1000+(i % 1000)/100+(i % 100)/10+i % 10;
    		if(t>10000)
    			continue;
    		flag[t]=true;
    	}
    	for(int i=1;i<10000;i++){
    		if(flag[i]==false)
    			System.out.println(i);
    	}
    }
}