母函数hdu1085

直接来。(1+x+x^2...+)*(1+x^2+x^4+....)*(1+x^5+x^10+...)

求系数的模板 

        c[0]=1;
        for(int i = 0 ;i<3;i++){
            for(int j= 0 ;j<= a[i];j++)
            for(int k = 0 ;k+j*val[i]<=Max;k++){
                c1[k+j*val[i]]+=c[k];
            }
            for(int k =0 ;k<=Max;k++)
                c[k]=c1[k],c1[k]=0;
        }

#include <cstdio>
#include <cstring>
#include <cmath>
#include <algorithm>
#include <climits>
#include <string>
#include <iostream>
#include <map>
#include <cstdlib>
#include <list>
#include <set>
#include <queue>
#include <stack>
using namespace std;
int a[10];
int val[]={1,2,5};
int c[111111];
int c1[111111];
int main()
{
    while(scanf("%d%d%d",&a[0],&a[1],&a[2])!=EOF,a[0]+a[1]+a[2]){
        int Max =  val[0] *a[0]+val[1]*a[1]+val[2]*a[2];
        memset(c1,0,sizeof(c1));memset(c,0,sizeof(c));
        for(int i = 0 ;i<=a[0];i++)
            c[i] = 1;
        for(int i = 1 ;i<3;i++){
            for(int j= 0 ;j<= a[i];j++)
            for(int k = 0 ;k+j*val[i]<=Max;k++){
                c1[k+j*val[i]]+=c[k];
            }
            for(int k =0 ;k<=Max;k++)
                c[k]=c1[k],c1[k]=0;
        }
        int ans=0 ;
        for(int i =0 ;i<=Max+100;i++)
            if(!c[i]){
                ans=i;break;
            }
        printf("%d
",ans);
    }
    return 0;
}