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1671:Rhyme Schemes

Special Judge 特殊评判
题目描述
The rhyme scheme for a poem (or stanza of a longer poem) tells which lines of the poem rhyme with which other lines. For example, a limerick such as If computers that you build are quantum
Then spies of all factions will want 'em
Our codes will all fail
And they'll read our email
`Til we've crypto that's quantum and daunt 'em

Jennifer and Peter Shor (http://www.research.att.com/~shor/notapoet.html)

Has a rhyme scheme of aabba, indicating that the first, second and fifth lines rhyme and the third and fourth lines rhyme.
For a poem or stanza of four lines, there are 15 possible rhyme schemes:
aaaa, aaab, aaba, aabb, aabc, abaa, abab, abac, abba, abbb, abbc, abca, a bcb, abcc, and abcd.
Write a program to compute the number of rhyme schemes for a poem or stanza of N lines where N is an input value.
输入解释
Input will consist of a sequence of integers N, one per line, ending with a 0 (zero) to indicate the end of the data. N is the number of lines in a poem.
输出解释
For each input integer N, your program should output the value of N, followed by a space, followed by the number of rhyme schemes for a poem with N lines as a decimal integer with at least 12 correct significant digits (use double precision floating point for your computations).
输入样例
1
2
3
4
20
30
10
0
输出样例
1 1
2 2
3 5
4 15
20 51724158235372
30 846749014511809120000000
10 115975

该题目是Virtual Judge题目,来自 北京大学POJ

题目来源 Greater New York 2003

源链接: POJ-1671

最后修改于 2020-10-29T06:10:35+00:00 由爬虫自动更新

共提交 0

通过率 --%
时间上限 内存上限
1000 10000