# hdu 2189 悼念512汶川大地震遇难同胞——来生一起走 (母函数)

Posted by 111qqz on Friday, February 26, 2016

## TOC

http://acm.hdu.edu.cn/showproblem.php?pid=2189 题意：n个人可以分成若干组，每组人数都为素数，问有多少种分法。 思路：母函数。先预处理素数，记得多处理一点…

``````/* ***********************************************
Author :111qqz
Created Time :2016年02月26日 星期五 16时24分17秒
File Name :code/hdu/2189.cpp
************************************************ */

#include <cstdio>muhanshu
#include <cstring>
#include <iostream>
#include <algorithm>
#include <vector>
#include <queue>
#include <set>
#include <map>
#include <string>
#include <cmath>
#include <cstdlib>
#include <ctime>
#define fst first
#define sec second
#define lson l,m,rt<<1
#define rson m+1,r,rt<<1|1
#define ms(a,x) memset(a,x,sizeof(a))
typedef long long LL;
#define pi pair < int ,int >
#define MP make_pair

using namespace std;
const double eps = 1E-8;
const int dx4[4]={1,0,0,-1};
const int dy4[4]={0,-1,1,0};
const int inf = 0x3f3f3f3f;
const int N=155;
int pri[N];
int a[N],tmp[N];
int cnt;
int n;

bool judge ( int n)
{
if (n<=3) return true;
for ( int i = 2 ; i*i <= n ; i++)
{
if (n%i==0) return false;
}

return true;
}

void pre()
{
cnt  = 0;
for ( int i = 2 ; i <= 200 ;  i++)
{
if (judge(i))
pri[++cnt] = i;
}
}
int main()
{
#ifndef  ONLINE_JUDGE
freopen("code/in.txt","r",stdin);
#endif

int T;
pre();
scanf("%d",&T);
while (T--)
{
scanf("%d",&n);

ms(a,0);
for ( int i = 0 ; i <= n ; i+=2 )
{
a[i] = 1;
tmp[i] =  0;
}

for ( int i = 2 ; pri[i] <= n ; i++)
{
for ( int j = 0 ; j <= n ; j++)
{
for ( int k = 0 ; k + j <= n ; k +=pri[i])
{
tmp[j+k] +=a[j];
}
}
for ( int j = 0 ; j <= n ; j ++)
{
a[j] = tmp[j];
tmp[j] =  0;
}
}

printf("%d\n",a[n]);
}

#ifndef ONLINE_JUDGE
fclose(stdin);
#endif
return 0;
}
``````

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