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QOJ
ID | 题目 | 提交者 | 结果 | 用时 | 内存 | 语言 | 文件大小 | 提交时间 | 测评时间 |
---|---|---|---|---|---|---|---|---|---|
#383582 | #6736. Alice and Bob | youxiao# | AC ✓ | 115ms | 165488kb | C++20 | 1.0kb | 2024-04-09 15:37:13 | 2024-04-09 15:37:14 |
Judging History
answer
#include<bits/stdc++.h>
using namespace std;
#define ll long long
const int N=11000000;
const double eps=1e-5;
const int mod=998244353;
#define endl '\n'
ll ksm(ll a,ll b,ll p=mod){
ll res=1;
for(;b;b>>=1,a=a*a%p){
if(b&1)res=a*res%p;
}
return res;
}
ll fac[N],infac[N];
void init(){
fac[0]=fac[1]=1;
for(int i=2;i<=10000000;i++)fac[i]=fac[i-1]*i%mod;
infac[10000000]=ksm(fac[10000000],mod-2);
for(int i=10000000;i>=1;i--)infac[i-1]=infac[i]*i%mod;
}
int main(){
#ifdef LOCAL
freopen("input.in","r",stdin);
freopen("output.out","w",stdout);
#endif
ios::sync_with_stdio(0),cin.tie(0),cout.tie(0);
int n;
init();
cin>>n;
ll ans=0;
for(int i=1;i<=n;i++){
if(n-i<i-1){
// ans=ans+fac[n-1];
// if(ans>=mod)ans%=mod;
}
else{
ans=ans+((fac[n-i]*fac[n-1-(i-1)]%mod*infac[n-i-(i-1)])%mod+mod);
if(ans>=mod)ans%=mod;
}
}
cout<<ans<<endl;
}
详细
Test #1:
score: 100
Accepted
time: 79ms
memory: 162904kb
input:
1
output:
1
result:
ok 1 number(s): "1"
Test #2:
score: 0
Accepted
time: 49ms
memory: 161960kb
input:
2
output:
1
result:
ok 1 number(s): "1"
Test #3:
score: 0
Accepted
time: 83ms
memory: 165408kb
input:
10
output:
997920
result:
ok 1 number(s): "997920"
Test #4:
score: 0
Accepted
time: 99ms
memory: 162344kb
input:
100
output:
188898954
result:
ok 1 number(s): "188898954"
Test #5:
score: 0
Accepted
time: 98ms
memory: 163612kb
input:
4
output:
10
result:
ok 1 number(s): "10"
Test #6:
score: 0
Accepted
time: 55ms
memory: 162392kb
input:
8
output:
12336
result:
ok 1 number(s): "12336"
Test #7:
score: 0
Accepted
time: 59ms
memory: 163660kb
input:
16
output:
373118483
result:
ok 1 number(s): "373118483"
Test #8:
score: 0
Accepted
time: 74ms
memory: 161624kb
input:
32
output:
314585464
result:
ok 1 number(s): "314585464"
Test #9:
score: 0
Accepted
time: 94ms
memory: 162848kb
input:
64
output:
627827331
result:
ok 1 number(s): "627827331"
Test #10:
score: 0
Accepted
time: 83ms
memory: 161920kb
input:
128
output:
828497685
result:
ok 1 number(s): "828497685"
Test #11:
score: 0
Accepted
time: 82ms
memory: 161692kb
input:
256
output:
65697890
result:
ok 1 number(s): "65697890"
Test #12:
score: 0
Accepted
time: 67ms
memory: 162152kb
input:
512
output:
854187619
result:
ok 1 number(s): "854187619"
Test #13:
score: 0
Accepted
time: 69ms
memory: 162856kb
input:
1024
output:
513823539
result:
ok 1 number(s): "513823539"
Test #14:
score: 0
Accepted
time: 70ms
memory: 162056kb
input:
1361956
output:
617368199
result:
ok 1 number(s): "617368199"
Test #15:
score: 0
Accepted
time: 79ms
memory: 161856kb
input:
7579013
output:
827172636
result:
ok 1 number(s): "827172636"
Test #16:
score: 0
Accepted
time: 61ms
memory: 165488kb
input:
8145517
output:
710624331
result:
ok 1 number(s): "710624331"
Test #17:
score: 0
Accepted
time: 107ms
memory: 165332kb
input:
6140463
output:
707600568
result:
ok 1 number(s): "707600568"
Test #18:
score: 0
Accepted
time: 110ms
memory: 163016kb
input:
3515281
output:
698302413
result:
ok 1 number(s): "698302413"
Test #19:
score: 0
Accepted
time: 105ms
memory: 162552kb
input:
6969586
output:
69470392
result:
ok 1 number(s): "69470392"
Test #20:
score: 0
Accepted
time: 92ms
memory: 162880kb
input:
2888636
output:
433579983
result:
ok 1 number(s): "433579983"
Test #21:
score: 0
Accepted
time: 115ms
memory: 161972kb
input:
9999998
output:
758172780
result:
ok 1 number(s): "758172780"
Test #22:
score: 0
Accepted
time: 111ms
memory: 162464kb
input:
9999999
output:
605195495
result:
ok 1 number(s): "605195495"
Test #23:
score: 0
Accepted
time: 63ms
memory: 162276kb
input:
10000000
output:
866813682
result:
ok 1 number(s): "866813682"