# hdu 1398 Square Coins (母函数裸题)

Posted by 111qqz on Thursday, February 25, 2016

## TOC

http://acm.hdu.edu.cn/showproblem.php?pid=1398 题意：所有的货币都是平方数，比如1,4,9…问凑出n块钱有多少种办法。 思路：母函数。

``````/* ***********************************************
Author :111qqz
Created Time :2016年02月25日 星期四 22时15分31秒
File Name :code/hdu/1398.cpp
************************************************ */

#include <cstdio>
#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=305;
int a[N],tmp[N];
int n;
int main()
{
#ifndef  ONLINE_JUDGE
freopen("code/in.txt","r",stdin);
#endif

while (scanf("%d",&n)!=EOF&&n)
{
for (int i = 0 ; i <=  n ;i++)
{
a[i] = 1;
tmp[i] = 0 ;
}

for ( int i = 2 ; i*i <= n ; i ++)
{
for ( int j = 0 ; j <= n ; j++)
{
for ( int k = 0 ; k+j <= n ; k+=i*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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