bzoj4591 【Shoi2015】超能粒子炮·改

由Lucas定理C(n,k)=C(n/2333,k/2333)*C(n%2333,k%2333)%2333

则ans=ΣC(n,i),(i<=k)

    =C(n/2333,0)*C(n%2333,0)+C(n/2333,0)*C(n%2333,1)+...+C(n/2333,0)*C(n%2333,2332)

    +C(n/2333,1)*C(n%2333,0)+C(n/2333,1)*C(n%2333,1)+...+C(n/2333,1)*C(n%2333,2332)

    +.....

    +C(n/2333,k/2333)*C(n%2333,0)+....+C(n/2333,k/2333)*C(n%2333,k%2333)

    =∑C(n/2333,j)*sum[n%2333][2332]+C(n/2333,k/2333)*sum[n%2333][k%2333],(0<=j<k/2333)

cal(n,k)=cal(n/2333,k/2333-1)*sum[n%2333][2332]+Lucas(n/2333,k/2333)*sum[n%2333][k%2333]

#include<iostream>
#include<algorithm>
#include<cstdio>
#include<cstring>
#define int long long
using namespace std;
const int p=;
int T,c[p+][p+],sum[p+][p+];
int Lucas(int a,int b)
{
if(a<||b<) return ;
if(a<p&&b<p) return c[a][b];
return Lucas(a/p,b/p)*c[a%p][b%p]%p;
}
int cal(int n,int k)
{
if(k<) return ;
return (cal(n/p,k/p-)*sum[n%p][p-]+Lucas(n/p,k/p)*sum[n%p][k%p])%p;
}
void pre()
{
c[][]=;sum[][]=; for(int i=;i<p;i++) c[i][]=,sum[i][]=,sum[][i]=;
for(int i=;i<p;i++) for(int j=;j<=i;j++) c[i][j]=(c[i-][j-]+c[i-][j])%p;
for(int i=;i<p;i++) for(int j=;j<p;j++) sum[i][j]=sum[i][j-]+c[i][j];
}
signed main()
{
pre();
scanf("%lld",&T);
while(T--)
{
int n,k;
scanf("%lld%lld",&n,&k);
printf("%lld\n",cal(n,k));
}
return ;
}
上一篇:rabbitmq之amqp queue


下一篇:TiDB初步概念