题目链接:
http://poj.org/problem?id=1316
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.
Sample Input
Sample Output
135792031425364 | | <-- a lot more numbers |9903991499259927993899499960997199829993 Hint 题意: 就是让你求1到10000以内所有的自私数,什么叫自私数?如果一个数不能分解为另一个数和那个数各位数字之和,它就是一个"自私数",举个例子,57可以是51+5+1来得到,那么57就不是自私数。那么100以内的自私数是:1,3,5,7,9,20,31,42,53,64,75,86和97。 题解: 直接把1到10000的非自私数打表存起来就行了。 代码:
#include#include #include #include using namespace std;#define met(a,b) memset(a,b,sizeof(a))const int maxn = 1e4;int a[maxn];int main(){ met(a,0); for(int i=1;i