QOJ.ac
QOJ
ID | Problem | Submitter | Result | Time | Memory | Language | File size | Submit time | Judge time |
---|---|---|---|---|---|---|---|---|---|
#56346 | #1423. Bin | tricyzhkx | AC ✓ | 2619ms | 23964kb | C++14 | 1.9kb | 2022-10-18 21:10:15 | 2022-10-18 21:10:16 |
Judging History
answer
# include <bits/stdc++.h>
using namespace std;
const int mod=998244353,g=3,_2=(mod+1)/2;
typedef long long ll;
int K,f[1000010],F[2100000],G[2100000],rev[2100000],w[2100000],maxn;
int add(int a,int b){return (a+=b)>=mod?a-mod:a;}
ll power(ll a,int b)
{
ll ans=1;
for(;b;b>>=1,a=a*a%mod)
if(b&1) ans=ans*a%mod;
return ans;
}
void init(int len)
{
int l=0;maxn=1;
while(maxn<=len) maxn<<=1,l++;
for(int i=0;i<maxn;i++) rev[i]=(rev[i>>1]>>1)|((i&1)<<(l-1));
for(int i=1;i<maxn;i<<=1)
{
ll wm=power(g,(mod-1)/(i<<1));w[i]=1;
for(int j=1;j<i;j++) w[i+j]=w[i+j-1]*wm%mod;
}
}
void NTT(int *a,bool flag)
{
for(int i=0;i<maxn;i++)
if(i<rev[i]) swap(a[i],a[rev[i]]);
for(int i=1;i<maxn;i<<=1)
for(int j=0;j<maxn;j+=i<<1)
for(int k=j;k<j+i;k++)
{
int x=a[k],y=(ll)w[i+k-j]*a[k+i]%mod;
a[k]=add(x,y);a[k+i]=add(x,mod-y);
}
if(!flag)
{
int inv=power(maxn,mod-2);
reverse(a+1,a+maxn);
for(int i=0;i<maxn;i++) a[i]=(ll)a[i]*inv%mod;
}
}
void solve(int l,int r)
{
if(l==r)
{
if(l<=1) return;
if(!(l&1)) f[l]=(f[l]+(ll)f[l/2]*f[l/2])%mod;
f[l]=(ll)_2*f[l]%mod;
for(int i=l/2+1;i<=min((l+K)/2,l-1);i++) f[l]=(f[l]+(ll)f[i]*f[l-i])%mod;
return;
}
int mid=(l+r)/2;
solve(l,mid);
if(!l)
{
for(int i=0;i<=mid;i++) F[i]=f[i];
init(mid<<1);
NTT(F,1);
for(int i=0;i<maxn;i++) F[i]=(ll)F[i]*F[i]%mod;
NTT(F,0);
for(int i=mid+1;i<=r;i++) f[i]=add(f[i],F[i]);
for(int i=0;i<maxn;i++) F[i]=0;
}
else
{
for(int i=l;i<=mid;i++) F[i-l]=f[i];
for(int i=0;i<=r-l;i++) G[i]=f[i];
init(mid-l+r-l);
NTT(F,1);NTT(G,1);
for(int i=0;i<maxn;i++) F[i]=(ll)F[i]*G[i]%mod;
NTT(F,0);
for(int i=mid+1;i<=r;i++) f[i]=(f[i]+2ll*F[i-l])%mod;
for(int i=0;i<maxn;i++) F[i]=G[i]=0;
}
solve(mid+1,r);
}
int main()
{
int n;f[1]=1;
cin>>n>>K;
solve(0,n);
cout<<f[n]<<endl;
return 0;
}
Details
Tip: Click on the bar to expand more detailed information
Test #1:
score: 100
Accepted
time: 3ms
memory: 3600kb
input:
2 0
output:
1
result:
ok 1 number(s): "1"
Test #2:
score: 0
Accepted
time: 1ms
memory: 3468kb
input:
3 0
output:
1
result:
ok 1 number(s): "1"
Test #3:
score: 0
Accepted
time: 2ms
memory: 3616kb
input:
3 1
output:
2
result:
ok 1 number(s): "2"
Test #4:
score: 0
Accepted
time: 2ms
memory: 3592kb
input:
4 0
output:
2
result:
ok 1 number(s): "2"
Test #5:
score: 0
Accepted
time: 2ms
memory: 3704kb
input:
4 1
output:
3
result:
ok 1 number(s): "3"
Test #6:
score: 0
Accepted
time: 2ms
memory: 3752kb
input:
4 2
output:
5
result:
ok 1 number(s): "5"
Test #7:
score: 0
Accepted
time: 2ms
memory: 3616kb
input:
6 2
output:
23
result:
ok 1 number(s): "23"
Test #8:
score: 0
Accepted
time: 1ms
memory: 3608kb
input:
7 42
output:
132
result:
ok 1 number(s): "132"
Test #9:
score: 0
Accepted
time: 2ms
memory: 3680kb
input:
10 1
output:
400
result:
ok 1 number(s): "400"
Test #10:
score: 0
Accepted
time: 2ms
memory: 3588kb
input:
13 4
output:
42003
result:
ok 1 number(s): "42003"
Test #11:
score: 0
Accepted
time: 2ms
memory: 3680kb
input:
239 17
output:
385818773
result:
ok 1 number(s): "385818773"
Test #12:
score: 0
Accepted
time: 108ms
memory: 4788kb
input:
50216 58
output:
744498776
result:
ok 1 number(s): "744498776"
Test #13:
score: 0
Accepted
time: 2440ms
memory: 23044kb
input:
787788 78
output:
394429402
result:
ok 1 number(s): "394429402"
Test #14:
score: 0
Accepted
time: 2ms
memory: 3612kb
input:
5 92
output:
14
result:
ok 1 number(s): "14"
Test #15:
score: 0
Accepted
time: 2ms
memory: 3708kb
input:
88 79
output:
931161641
result:
ok 1 number(s): "931161641"
Test #16:
score: 0
Accepted
time: 3ms
memory: 3700kb
input:
749 77
output:
615055472
result:
ok 1 number(s): "615055472"
Test #17:
score: 0
Accepted
time: 5ms
memory: 3772kb
input:
2281 89
output:
282226588
result:
ok 1 number(s): "282226588"
Test #18:
score: 0
Accepted
time: 11ms
memory: 3852kb
input:
5765 35
output:
293680396
result:
ok 1 number(s): "293680396"
Test #19:
score: 0
Accepted
time: 53ms
memory: 4768kb
input:
43189 12
output:
805295564
result:
ok 1 number(s): "805295564"
Test #20:
score: 0
Accepted
time: 2371ms
memory: 23008kb
input:
806855 5
output:
593114139
result:
ok 1 number(s): "593114139"
Test #21:
score: 0
Accepted
time: 2551ms
memory: 23736kb
input:
994514 45
output:
678426421
result:
ok 1 number(s): "678426421"
Test #22:
score: 0
Accepted
time: 2558ms
memory: 23812kb
input:
999921 62
output:
752162081
result:
ok 1 number(s): "752162081"
Test #23:
score: 0
Accepted
time: 2606ms
memory: 23744kb
input:
995033 94
output:
130314865
result:
ok 1 number(s): "130314865"
Test #24:
score: 0
Accepted
time: 2541ms
memory: 23656kb
input:
901438 97
output:
809128292
result:
ok 1 number(s): "809128292"
Test #25:
score: 0
Accepted
time: 2485ms
memory: 23800kb
input:
993020 0
output:
926771801
result:
ok 1 number(s): "926771801"
Test #26:
score: 0
Accepted
time: 2619ms
memory: 23964kb
input:
1000000 100
output:
470305140
result:
ok 1 number(s): "470305140"