树 51nod1412

#include <iostream>
#include <cstdio>
#include <cstring>
#include <vector>
#include <queue>
#include <map>
#include <string>
using namespace std;
typedef long long ll;
ll dp[2005][16];
const int mod=1e9+7;

void solve()
{
   dp[1][1]=1;
   dp[2][2]=2;
   int i,j,k;
   for(i=3;i<=2000;i++)
   {
      for(k=2;k<=15;k++)
      {
         for(j=0;j<i;j++)
         {
            dp[i][k]=(dp[i][k]+dp[i-1-j][k-1]*dp[j][k-1])%mod;
            dp[i][k]=(dp[i][k]+2*dp[i-1-j][k-2]*dp[j][k-1])%mod;
         }
      }
   }
}

int main()
{
   int n,i;
   long long ans;
   solve();
   while(scanf("%d",&n)!=EOF)
   {
      ans=0;
      for(i=1;i<=15;i++) ans=(ans+dp[n][i])%mod;
      printf("%lld\n",ans);
   }
   return 0;
}

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转载自blog.csdn.net/hi_One_Month/article/details/72620858
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