QOJ.ac
QOJ
ID | Problem | Submitter | Result | Time | Memory | Language | File size | Submit time | Judge time |
---|---|---|---|---|---|---|---|---|---|
#407294 | #6736. Alice and Bob | SanCai# | AC ✓ | 141ms | 159904kb | C++14 | 1.2kb | 2024-05-08 14:31:21 | 2024-05-08 14:31:23 |
Judging History
answer
#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
#define lowbit(x) ((x)&(-x))
#define endl '\n'
#define sc scanf
#define pt printf
#define YES cout<<"YES"<<endl;
#define NO cout<<"NO"<<endl;
#define ls k+k
#define rs k+k+1
using pll = pair<ll, ll>;
using pii = pair<int, int>;
const int N = 1e7 + 10;
const ll p=998244353;
ll fac[N],inv[N];
ll C(ll n,ll m)
{
if(m>n)return 0;
if(m==0&&n==0)return 1;
return (fac[n]*inv[m]%p)*inv[n-m]%p;
}
ll qp(ll a,ll b)
{
a=a%p;
ll res=1;
while(b)
{
if(b&1)res=res*a%p;
a=a*a%p;
b>>=1;
}
return res;
}
void UraykevoliQwQ()
{
int n;cin>>n;
ll ans=0;
fac[0]=fac[1]=inv[0]=inv[1]=1;
for(int i=1;i<=n;i++)
{
fac[i]=fac[i-1]*i%p;
//inv[i]=qp(fac[i],p-2);
}
//for(int i=2;i<=n;i++)inv[i]=(ll)(p-p/i)*inv[p%i]%p;
inv[n]=qp(fac[n],p-2);
for(int i=n-1;i>=1;i--)
{
inv[i]=(i+1)*inv[i+1]%p;
}
//for(int i=n-1;i>=1;i--)
//{
// inv[i]=i*inv[i+1]%p;
//}
for(int i=1;i<=n;i++)
{
ans=(ans+((C(n-i,i-1)*fac[i-1]%p)*fac[n-i])%p)%p;
}
cout<<ans<<endl;
}
int main()
{
ios::sync_with_stdio(false), cin.tie(nullptr), cout.tie(nullptr);
//int _;cin>>_;while(_--)
UraykevoliQwQ();
return 0;
}
Details
Tip: Click on the bar to expand more detailed information
Test #1:
score: 100
Accepted
time: 1ms
memory: 5516kb
input:
1
output:
1
result:
ok 1 number(s): "1"
Test #2:
score: 0
Accepted
time: 1ms
memory: 5556kb
input:
2
output:
1
result:
ok 1 number(s): "1"
Test #3:
score: 0
Accepted
time: 0ms
memory: 5708kb
input:
10
output:
997920
result:
ok 1 number(s): "997920"
Test #4:
score: 0
Accepted
time: 1ms
memory: 5644kb
input:
100
output:
188898954
result:
ok 1 number(s): "188898954"
Test #5:
score: 0
Accepted
time: 1ms
memory: 5576kb
input:
4
output:
10
result:
ok 1 number(s): "10"
Test #6:
score: 0
Accepted
time: 1ms
memory: 5652kb
input:
8
output:
12336
result:
ok 1 number(s): "12336"
Test #7:
score: 0
Accepted
time: 1ms
memory: 5644kb
input:
16
output:
373118483
result:
ok 1 number(s): "373118483"
Test #8:
score: 0
Accepted
time: 1ms
memory: 5568kb
input:
32
output:
314585464
result:
ok 1 number(s): "314585464"
Test #9:
score: 0
Accepted
time: 0ms
memory: 5568kb
input:
64
output:
627827331
result:
ok 1 number(s): "627827331"
Test #10:
score: 0
Accepted
time: 0ms
memory: 5660kb
input:
128
output:
828497685
result:
ok 1 number(s): "828497685"
Test #11:
score: 0
Accepted
time: 1ms
memory: 5564kb
input:
256
output:
65697890
result:
ok 1 number(s): "65697890"
Test #12:
score: 0
Accepted
time: 1ms
memory: 5708kb
input:
512
output:
854187619
result:
ok 1 number(s): "854187619"
Test #13:
score: 0
Accepted
time: 1ms
memory: 5552kb
input:
1024
output:
513823539
result:
ok 1 number(s): "513823539"
Test #14:
score: 0
Accepted
time: 19ms
memory: 27084kb
input:
1361956
output:
617368199
result:
ok 1 number(s): "617368199"
Test #15:
score: 0
Accepted
time: 111ms
memory: 124960kb
input:
7579013
output:
827172636
result:
ok 1 number(s): "827172636"
Test #16:
score: 0
Accepted
time: 113ms
memory: 134868kb
input:
8145517
output:
710624331
result:
ok 1 number(s): "710624331"
Test #17:
score: 0
Accepted
time: 81ms
memory: 102068kb
input:
6140463
output:
707600568
result:
ok 1 number(s): "707600568"
Test #18:
score: 0
Accepted
time: 56ms
memory: 60616kb
input:
3515281
output:
698302413
result:
ok 1 number(s): "698302413"
Test #19:
score: 0
Accepted
time: 83ms
memory: 115608kb
input:
6969586
output:
69470392
result:
ok 1 number(s): "69470392"
Test #20:
score: 0
Accepted
time: 31ms
memory: 52408kb
input:
2888636
output:
433579983
result:
ok 1 number(s): "433579983"
Test #21:
score: 0
Accepted
time: 126ms
memory: 159764kb
input:
9999998
output:
758172780
result:
ok 1 number(s): "758172780"
Test #22:
score: 0
Accepted
time: 133ms
memory: 159876kb
input:
9999999
output:
605195495
result:
ok 1 number(s): "605195495"
Test #23:
score: 0
Accepted
time: 141ms
memory: 159904kb
input:
10000000
output:
866813682
result:
ok 1 number(s): "866813682"