CF914H.Ember and Storm's Tree Game

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题目描述

Ember and Storm play a game. First, Ember picks a labelled tree TT of nn vertices, such that the degree of every vertex is at most dd . Then, Storm picks two distinct vertices uu and vv in this tree and writes down the labels of the vertices in the path from uu to vv in a sequence a1,a2... aka_{1},a_{2}...\ a_{k} . Finally, Ember picks any index ii ( 1<=i<k1<=i<k ) in the array. Now he performs one of the following two operations exactly once:

  • flip the subrange [i+1,k][i+1,k] and add aia_{i} to it. After this, the sequence becomes a1,... ai,ak+ai,ak1+ai,... ai+1+aia_{1},...\ a_{i},a_{k}+a_{i},a_{k-1}+a_{i},...\ a_{i+1}+a_{i}
  • negate the subrange [i+1,k][i+1,k] and add aia_{i} to it. i.e., the array becomes a1,... ai,ai+1+ai,ai+2+ai,...ak+aia_{1},...\ a_{i},-a_{i+1}+a_{i},-a_{i+2}+a_{i},...-a_{k}+a_{i}

Ember wins if the array is monotonically increasing or decreasing after this. Otherwise Storm wins.

The game can be described by the tuple (T,u,v,i,op)(T,u,v,i,op) where opop is «flip» or «negate» depending on the action Ember chose in the last turn. Find the number of tuples that can occur if Ember and Storm play optimally. When they play optimally, if there are multiple moves by which they are guaranteed to win, then they may play any of the winning moves. Otherwise, if someone loses no matter what they play, then they may play any of the possible moves.

Report the answer modulo mm .

输入格式

The input consists of a single line containing three integers nn , dd and mm ( 2<=n<=200,1<=d<n,1<=m<=21092<=n<=200,1<=d<n,1<=m<=2·10^{9} ).

输出格式

Print a single number — the number of possible tuples if Ember and Storm play as described, modulo mm .

输入输出样例

  • 输入#1

    2 1 1000000007
    

    输出#1

    4
    
  • 输入#2

    3 1 250
    

    输出#2

    0
    
  • 输入#3

    3 2 100
    

    输出#3

    36
    

说明/提示

In the first sample case, there is only one possible tree. There are two possible paths, 11 to 22 and 22 to 11 . For both paths, ii can only be 11 , and opop can take both possibilities. Therefore, the answer is 44 .

In the second sample, there are no possible trees.

In the third sample, there are three possible trees.

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