hdu_2110_Crisis of HDU(母函数)

题目连接：http://acm.hdu.edu.cn/showproblem.php?pid=2110

题意：给你N个价值和数目，求方案数，很裸的母函数。

#include<cstdio>
int c1[4000],c2[4000],all,pi[110],mi[110],su,i,j,k;
int mu(int sum){
    for(i=0;i<=sum;i++)c1[i]=0,c2[i]=0;
    for(i=0;i<=mi[1];i++)c1[pi[1]*i]=1;
    for(i=2;i<=all;i++){
        for(j=0;j<=mi[i];j++)
            for(k=0;pi[i]*j+k<=sum;k++)c2[pi[i]*j+k]+=c1[k]%10000;
        for(j=0;j<=sum;j++)c1[j]=c2[j]%10000,c2[j]=0;
    }
    return c1[sum];
}
int main(){
    while(~scanf("%d",&all),all){
        for(i=1,su=0;i<=all;i++)scanf("%d%d",&pi[i],&mi[i]),su+=pi[i]*mi[i];
        if(su%3)puts("sorry");
        else printf("%d\n",mu(su/3));
    }
    return 0;
}