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QOJ
ID | Problem | Submitter | Result | Time | Memory | Language | File size | Submit time | Judge time |
---|---|---|---|---|---|---|---|---|---|
#482138 | #9121. I Love Marathon Contest | Crysfly | AC ✓ | 440ms | 29440kb | C++17 | 4.0kb | 2024-07-17 17:32:55 | 2024-07-17 17:32:55 |
Judging History
answer
// what is matter? never mind.
#pragma GCC optimize("Ofast")
#pragma GCC optimize("unroll-loops")
//#pragma GCC target("sse,sse2,sse3,sse4,popcnt,abm,mmx,avx,avx2")
#include<bits/stdc++.h>
#define For(i,a,b) for(int i=(a);i<=(b);++i)
#define Rep(i,a,b) for(int i=(a);i>=(b);--i)
#define ll long long
//#define int long long
#define ull unsigned long long
#define SZ(x) ((int)((x).size()))
#define ALL(x) (x).begin(),(x).end()
using namespace std;
inline int read()
{
char c=getchar();int x=0;bool f=0;
for(;!isdigit(c);c=getchar())f^=!(c^45);
for(;isdigit(c);c=getchar())x=(x<<1)+(x<<3)+(c^48);
if(f)x=-x;return x;
}
#define mod 998244353
struct modint{
int x;
modint(int o=0){x=o;}
modint &operator = (int o){return x=o,*this;}
modint &operator +=(modint o){return x=x+o.x>=mod?x+o.x-mod:x+o.x,*this;}
modint &operator -=(modint o){return x=x-o.x<0?x-o.x+mod:x-o.x,*this;}
modint &operator *=(modint o){return x=1ll*x*o.x%mod,*this;}
modint &operator ^=(int b){
modint a=*this,c=1;
for(;b;b>>=1,a*=a)if(b&1)c*=a;
return x=c.x,*this;
}
modint &operator /=(modint o){return *this *=o^=mod-2;}
friend modint operator +(modint a,modint b){return a+=b;}
friend modint operator -(modint a,modint b){return a-=b;}
friend modint operator *(modint a,modint b){return a*=b;}
friend modint operator /(modint a,modint b){return a/=b;}
friend modint operator ^(modint a,int b){return a^=b;}
friend bool operator ==(modint a,modint b){return a.x==b.x;}
friend bool operator !=(modint a,modint b){return a.x!=b.x;}
bool operator ! () {return !x;}
modint operator - () {return x?mod-x:0;}
bool operator <(const modint&b)const{return x<b.x;}
};
inline modint qpow(modint x,int y){return x^y;}
vector<modint> fac,ifac,iv;
inline void initC(int n)
{
if(iv.empty())fac=ifac=iv=vector<modint>(2,1);
int m=iv.size(); ++n;
if(m>=n)return;
iv.resize(n),fac.resize(n),ifac.resize(n);
For(i,m,n-1){
iv[i]=iv[mod%i]*(mod-mod/i);
fac[i]=fac[i-1]*i,ifac[i]=ifac[i-1]*iv[i];
}
}
inline modint C(int n,int m){
if(m<0||n<m)return 0;
return initC(n),fac[n]*ifac[m]*ifac[n-m];
}
inline modint sign(int n){return (n&1)?(mod-1):(1);}
#define fi first
#define se second
#define pb push_back
#define mkp make_pair
typedef pair<int,int>pii;
typedef vector<int>vi;
#define maxn 200005
#define inf 0x3f3f3f3f
int n;
int b[maxn],bb[maxn];
modint res=0;
int cnt1,cnt0;
int sum[maxn];
int br(){
For(i,1,n*2)bb[i]=b[i];
int u=0,res=0,now=-1,cnt=n*2;
while(1){
if(u==n*2) u=1,++res;
else ++u;
if(cnt==0 && u==1) break;
if(b[u]==-now){
b[u]=0,now=-now;
--cnt;
}
// For(i,1,n*2)cout<<b[i]<<" "; cout<<"\n";
}
// cout<<res<<"\n";
For(i,1,n*2)b[i]=bb[i];
return res;
}
void chk(){
int mx=0,mn=0;
For(i,1,n*2){
sum[i]=sum[i-1]+b[i];
mx=max(mx,sum[i]),mn=min(mn,sum[i]);
}
// For(i,1,n*2) cout<<b[i]<<" "; cout<<"\n";
int ans=mx-mn;
{
bool ok=0;
Rep(i,n*2,0){
if(sum[i]==mn){
ok=0;
break;
}
if(sum[i]==mx){
ok=1;
break;
}
}
cnt1+=ok; cnt0+=(!ok);
ans+=ok;
}
// cout<<ans<<" "; cout<<"\n";
// int tmp=br();
// if(tmp!=ans)exit(2343);
res+=ans;
// if(mn<0)res+=1;
}
void dfs(int u,int u1,int u2){
if(u==2*n+1){
chk();
return;
}
if(u1) b[u]=1,dfs(u+1,u1-1,u2);
if(u2 && u>1) b[u]=-1,dfs(u+1,u1,u2-1);
}
modint divsum[maxn];
modint S(int n,int a){
modint res=0;
For(k,1,a+n)
res+=divsum[k]*C(n*2,n+a-k);
res/=C(n*2,n);
return res;
}
signed main()
{
n=read(); initC(n*2);
// For(i,1,n*2)
// for(int j=i;j<=n*2;j+=i) divsum[j]+=1;
modint res=0;
res+=C(2*n-1,n-1);
For(i,1,n-1) res+=C(2*n-1,n+i);
For(i,1,n-1) res+=2*C(2*n-2,n-1-i);
// modint tmp=((n+1)*S(n,1)-2*S(n,0)+S(n,-1))-1;
// tmp*=C(n*2,n)*iv[n+1];
// res-=tmp;
For(i,1,n-1) For(k,1,n/(i+1)) {
res-=C(2*n-2,n-k*(i+1));
res+=2*C(2*n-2,n-1-k*(i+1));
res-=C(2*n-2,n-2-k*(i+1));
}
res*=2,res*=fac[n]*fac[n];
cout<<res.x;
return 0;
}
/*
*/
Details
Tip: Click on the bar to expand more detailed information
Test #1:
score: 100
Accepted
time: 1ms
memory: 4596kb
input:
1
output:
2
result:
ok "2"
Test #2:
score: 0
Accepted
time: 1ms
memory: 6172kb
input:
2
output:
40
result:
ok "40"
Test #3:
score: 0
Accepted
time: 1ms
memory: 5952kb
input:
3
output:
1656
result:
ok "1656"
Test #4:
score: 0
Accepted
time: 0ms
memory: 4376kb
input:
4
output:
112896
result:
ok "112896"
Test #5:
score: 0
Accepted
time: 1ms
memory: 4256kb
input:
5
output:
11750400
result:
ok "11750400"
Test #6:
score: 0
Accepted
time: 1ms
memory: 6012kb
input:
6
output:
741506047
result:
ok "741506047"
Test #7:
score: 0
Accepted
time: 1ms
memory: 4400kb
input:
7
output:
663688356
result:
ok "663688356"
Test #8:
score: 0
Accepted
time: 1ms
memory: 4372kb
input:
8
output:
564862407
result:
ok "564862407"
Test #9:
score: 0
Accepted
time: 1ms
memory: 6084kb
input:
9
output:
161774290
result:
ok "161774290"
Test #10:
score: 0
Accepted
time: 1ms
memory: 4264kb
input:
10
output:
652045233
result:
ok "652045233"
Test #11:
score: 0
Accepted
time: 1ms
memory: 5932kb
input:
11
output:
748014862
result:
ok "748014862"
Test #12:
score: 0
Accepted
time: 1ms
memory: 4368kb
input:
12
output:
304641307
result:
ok "304641307"
Test #13:
score: 0
Accepted
time: 1ms
memory: 6404kb
input:
13
output:
729875009
result:
ok "729875009"
Test #14:
score: 0
Accepted
time: 1ms
memory: 4332kb
input:
14
output:
711836922
result:
ok "711836922"
Test #15:
score: 0
Accepted
time: 1ms
memory: 6320kb
input:
15
output:
920550523
result:
ok "920550523"
Test #16:
score: 0
Accepted
time: 6ms
memory: 6580kb
input:
17408
output:
632438437
result:
ok "632438437"
Test #17:
score: 0
Accepted
time: 16ms
memory: 5008kb
input:
46789
output:
458137544
result:
ok "458137544"
Test #18:
score: 0
Accepted
time: 5ms
memory: 5968kb
input:
22610
output:
356200349
result:
ok "356200349"
Test #19:
score: 0
Accepted
time: 7ms
memory: 4576kb
input:
33916
output:
52946419
result:
ok "52946419"
Test #20:
score: 0
Accepted
time: 12ms
memory: 6220kb
input:
37395
output:
66208794
result:
ok "66208794"
Test #21:
score: 0
Accepted
time: 233ms
memory: 18344kb
input:
564256
output:
145325890
result:
ok "145325890"
Test #22:
score: 0
Accepted
time: 346ms
memory: 23428kb
input:
834557
output:
942727699
result:
ok "942727699"
Test #23:
score: 0
Accepted
time: 288ms
memory: 20324kb
input:
700474
output:
110750834
result:
ok "110750834"
Test #24:
score: 0
Accepted
time: 214ms
memory: 16244kb
input:
530345
output:
407205453
result:
ok "407205453"
Test #25:
score: 0
Accepted
time: 399ms
memory: 26000kb
input:
942062
output:
849740307
result:
ok "849740307"
Test #26:
score: 0
Accepted
time: 256ms
memory: 18608kb
input:
629156
output:
521070781
result:
ok "521070781"
Test #27:
score: 0
Accepted
time: 363ms
memory: 24000kb
input:
861230
output:
52253753
result:
ok "52253753"
Test #28:
score: 0
Accepted
time: 261ms
memory: 20252kb
input:
643760
output:
896717464
result:
ok "896717464"
Test #29:
score: 0
Accepted
time: 371ms
memory: 24428kb
input:
877036
output:
148107554
result:
ok "148107554"
Test #30:
score: 0
Accepted
time: 291ms
memory: 19744kb
input:
672739
output:
384285823
result:
ok "384285823"
Test #31:
score: 0
Accepted
time: 427ms
memory: 28512kb
input:
999991
output:
11040806
result:
ok "11040806"
Test #32:
score: 0
Accepted
time: 425ms
memory: 27260kb
input:
999992
output:
10247994
result:
ok "10247994"
Test #33:
score: 0
Accepted
time: 440ms
memory: 27244kb
input:
999993
output:
288885449
result:
ok "288885449"
Test #34:
score: 0
Accepted
time: 427ms
memory: 27440kb
input:
999994
output:
488915584
result:
ok "488915584"
Test #35:
score: 0
Accepted
time: 423ms
memory: 29436kb
input:
999995
output:
913096398
result:
ok "913096398"
Test #36:
score: 0
Accepted
time: 430ms
memory: 29440kb
input:
999996
output:
125855903
result:
ok "125855903"
Test #37:
score: 0
Accepted
time: 423ms
memory: 27316kb
input:
999997
output:
616335312
result:
ok "616335312"
Test #38:
score: 0
Accepted
time: 425ms
memory: 29336kb
input:
999998
output:
381708275
result:
ok "381708275"
Test #39:
score: 0
Accepted
time: 422ms
memory: 27236kb
input:
999999
output:
513037643
result:
ok "513037643"
Test #40:
score: 0
Accepted
time: 425ms
memory: 29372kb
input:
1000000
output:
252793281
result:
ok "252793281"
Extra Test:
score: 0
Extra Test Passed