bzoj1655 [Usaco2006 Jan] Dollar Dayz 奶牛商店(完全背包+高精)

#include <cstdio>
#include <cstring>
int n,m;
inline int max(int x,int y){return x>y?x:y;}
struct bigint{
int a[50],digit;
bigint(){memset(a,0,sizeof(a));digit=0;}
bigint operator +=(bigint x){
int tot=max(digit,x.digit);
for(int i=1;i<=tot;++i){
a[i]+=x.a[i];
a[i+1]+=a[i]/10;a[i]%=10;
}
if(a[tot+1]) digit=tot+1;else digit=tot;
}
}f[1005];
int main(){
//  freopen("a.in","r",stdin);
scanf("%d%d",&m,&n);
f[0].a[1]=1;f[0].digit=1;
for(int i=1;i<=n;++i)
for(int j=i;j<=m;++j)
f[j]+=f[j-i];
for(int i=f[m].digit;i>=1;--i) printf("%d",f[m].a[i]);puts("");
return 0;
}