10143 - 等差数列

一个等差数列是一个能表示成a, a+b, a+2b,..., a+nb (n=0,1,2,3,...) 在这个问题中a是一个非负的整数,b是正整数。 写一个程序来找出在双平方数集合S中长度为n的等差数列。 双平方数集合是所有能表示成p2+q2的数的集合。

输入

第一行: N(3<= N<=25),要找的等差数列的长度。
第二行: M(1<= M<=250),搜索双平方数的上界0 <= p,q <= M。

输出

如果没有找到数列,输出`NONE'。 如果找到了,输出一行或多行, 每行由于二个整数组成:a,b 这些行应该先按b排序再按a排序。 将不会有只多于10,000个等差数列。

样例

输入

5
7

输出

1 4
37 4
2 8
29 8
1 12
5 12
13 12
17 12
5 20
2 24

提示

Arithmetic Progressions

An arithmetic progression is a sequence of the form a, a+b, a+2b, ..., a+nb where n=0,1,2,3,... . For this problem, a is a non-negative integer and b is a positive integer.

Write a program that finds all arithmetic progressions of length n in the set S of bisquares. The set of bisquares is defined as the set of all integers of the form p2 + q2 (where p and q are non-negative integers).

PROGRAM NAME: ariprog INPUT FORMAT Line 1: N (3 <= N <= 25), the length of progressions for which to search
Line 2: M (1 <= M <= 250), an upper bound to limit the search to the bisquares with 0 <= p,q <= M.

SAMPLE INPUT (file ariprog.in) 5 7

OUTPUT FORMAT If no sequence is found, a singe line reading `NONE'. Otherwise, output one or more lines, each with two integers: the first element in a found sequence and the difference between consecutive elements in the same sequence. The lines should be ordered with smallest-difference sequences first and smallest starting number within those sequences first.

There will be no more than 10,000 sequences.

SAMPLE OUTPUT (file ariprog.out) 1 4 37 4 2 8 29 8 1 12 5 12 13 12 17 12 5 20 2 24

时间限制 1 秒
内存限制 128 MB
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