我，ycl:BM是什么早就忘了！
毕老爷:那你们可以做一做这道题练练BM板子啊。
1 //Achen
2 #include<bits/stdc++.h>
3 #define For(i,a,b) for(int i=(a);i<=(b);i++)
4 #define Rep(i,a,b) for(int i=(a);i>=(b);i--)
5 #define Formylove return 0
6 const int N=1e5+7,p=1e9+7;
7 typedef long long LL;
8 typedef double db;
9 using namespace std;
10 int n,m;
11 LL f[15007][5007];
12
13 template<typename T> void read(T &x) {
14 char ch=getchar(); T f=1; x=0;
15 while(ch!='-'&&(ch<'0'||ch>'9')) ch=getchar();
16 if(ch=='-') f=-1,ch=getchar();
17 for(;ch>='0'&&ch<='9';ch=getchar()) x=x*10+ch-'0'; x*=f;
18 }
19
20 int main() {
21 freopen("1.in","r",stdin);
22 //freopen("biao.in","w",stdout);
23 read(m); read(n);
24 For(i,1,m) f[1][i]=1;
25 For(i,1,n) {
26 if(i>1) For(j,1,m) f[i][j]=f[i-1][m-j];
27 For(j,1,m) f[i][j]=(f[i][j]+f[i][j-1])%p;
28 }
29 printf("%lld
",f[14555][m]);
30 //printf("%d
",n);
31 //For(i,1,n) printf("%lld ",f[i][m]);
32 //printf("%lld
",f[n][m]);
33 Formylove;
34 }
//Achen
#include<algorithm>
#include<iostream>
#include<cstring>
#include<cstdlib>
#include<vector>
#include<cstdio>
#include<queue>
#include<cmath>
#include<set>
#include<map>
#define Formylove return 0
#define For(i,a,b) for(int i=(a);i<=(b);i++)
#define Rep(i,a,b) for(int i=(a);i>=(b);i--)
const int N=15007,p=1e9+7;
typedef long long LL;
typedef double db;
using namespace std;
int n,cnt,fail[N];
vector<LL>f[N];
LL a[N],delta[N];
template<typename T>void read(T &x) {
char ch=getchar(); x=0; T f=1;
while(ch!='-'&&(ch<'0'||ch>'9')) ch=getchar();
if(ch=='-') f=-1,ch=getchar();
for(;ch>='0'&&ch<='9';ch=getchar()) x=x*10+ch-'0'; x*=f;
}
LL ksm(LL a,LL b) {
LL rs=1,bs=a%p;
while(b) {
if(b&1) rs=rs*bs%p;
bs=bs*bs%p;
b>>=1;
}
return rs;
}
#define ANS
int main() {
#ifdef ANS
freopen("biao.in","r",stdin);
freopen("shizi.out","w",stdout);
#endif
read(n);
For(i,1,n) read(a[i]);
For(i,1,n) {
LL tp=0; int up=f[cnt].size();
For(j,0,up-1) tp=(tp+f[cnt][j]*a[i-j-1]%p)%p;
if(tp==a[i]) continue;
delta[i]=(a[i]-tp+p)%p;
fail[cnt]=i;
++cnt;
if(cnt==1) {
f[cnt].resize(i);
continue;
}
LL mul=delta[i]*ksm(delta[fail[cnt-2]],p-2)%p,fmul=(p-mul)%p;
f[cnt].resize(i-fail[cnt-2]-1);
f[cnt].push_back(mul);
up=f[cnt-2].size();
For(j,0,up-1) f[cnt].push_back(fmul*f[cnt-2][j]%p);
up=f[cnt-1].size();
if(f[cnt].size()<f[cnt-1].size()) f[cnt].resize(up);
For(j,0,up-1) f[cnt][j]=(f[cnt][j]+f[cnt-1][j])%p;
}
int up=f[cnt].size();
printf("%d
",up);
For(i,0,up-1) printf("%lld ",f[cnt][i]);
Formylove;
}
1 //Achen
2 #include<bits/stdc++.h>
3 #define For(i,a,b) for(int i=(a);i<=(b);i++)
4 #define Rep(i,a,b) for(int i=(a);i>=(b);i--)
5 #define Formylove return 0
6 const int N=1e5+7,p=1e9+7;
7 typedef long long LL;
8 typedef double db;
9 using namespace std;
10 int cnt;
11 LL A[N],f[N],n;
12
13 template<typename T> void read(T &x) {
14 char ch=getchar(); T f=1; x=0;
15 while(ch!='-'&&(ch<'0'||ch>'9')) ch=getchar();
16 if(ch=='-') f=-1,ch=getchar();
17 for(;ch>='0'&&ch<='9';ch=getchar()) x=x*10+ch-'0'; x*=f;
18 }
19
20 LL rs[N],bs[N],tp[N];
21 void cheng(LL a[],LL b[]) {
22 For(i,0,cnt*2) tp[i]=0;
23 For(i,0,cnt-1) For(j,0,cnt-1)
24 (tp[i+j]+=a[i]*b[j])%=p;
25 Rep(i,cnt*2-2,cnt) if(tp[i])
26 For(j,0,cnt-1)
27 (tp[i-j-1]+=A[j]*tp[i]%p)%=p;
28 For(i,0,cnt-1) a[i]=tp[i];
29 }
30
31 void ksm(LL b) {
32 while(b) {
33 if(b&1) cheng(rs,bs);
34 cheng(bs,bs);
35 b>>=1;
36 }
37 }
38
39 int main() {
40 freopen("shizi.out","r",stdin);
41 //freopen("shizi.out","w",stdout);
42 read(cnt);
43 For(i,0,cnt-1) read(A[i]);
44 read(n);
45 rs[0]=1; bs[1]=1; ksm(n-1);
46 For(i,1,cnt) read(f[i]);
47 LL ans=0;
48 For(i,0,cnt-1) ans=(ans+f[i+1]*rs[i]%p)%p;
49 printf("%lld
",ans);
50 Formylove;
51 }