QOJ.ac
QOJ
ID | Problem | Submitter | Result | Time | Memory | Language | File size | Submit time | Judge time |
---|---|---|---|---|---|---|---|---|---|
#383940 | #6736. Alice and Bob | GordenGhost# | WA | 194ms | 159956kb | C++17 | 966b | 2024-04-09 19:04:08 | 2024-04-09 19:04:09 |
Judging History
answer
#include"bits/stdc++.h"
#define endl '\n'
using ll=long long;
using namespace std;
#define int ll
constexpr int N=10000000+5,mod=998244353;
ll fact[N],inv[N];
ll qpow(ll a,ll b,ll p){
a%=p;
ll ans=1%p;
for(;b;b>>=1){
if(b&1)
ans=ans*a%p;
a=a*a%p;
}
return ans;
}
void init(ll n,ll p){
fact[0]=1;
for(int i=1;i<=n;i++)
fact[i]=(fact[i-1]*i)%p;
inv[0]=qpow(1,mod-2,mod);
inv[1]=1;
for(int i=2;i<=N-5;i++){
inv[i]=(mod-mod/i)*inv[mod%i]%mod;
}
}
void slove(){
int n;
cin>>n;
init(N-5,mod);
ll ans=0;
if(n==1){
cout<<1<<endl;
return;
}
ll tot=1;
int j=n-1;
for(int i=1;i<=n/2;i++){
for(;j>=n-2*i+2;j--){
tot=(tot*j+mod)%mod;
tot%=mod;
}
ans=(ans+mod+tot*fact[n-i]%mod)%mod;
ans%=mod;
tot=(tot*inv[n-i]+mod)%mod;
tot%=mod;
}
cout<<ans<<endl;
}
signed main(){
cin.tie(nullptr)->sync_with_stdio(0);
int _=1;
// cin>>_;
while(_--){
slove();
}
return 0;
}
Details
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Test #1:
score: 100
Accepted
time: 133ms
memory: 159776kb
input:
1
output:
1
result:
ok 1 number(s): "1"
Test #2:
score: 0
Accepted
time: 126ms
memory: 159832kb
input:
2
output:
1
result:
ok 1 number(s): "1"
Test #3:
score: 0
Accepted
time: 79ms
memory: 159836kb
input:
10
output:
997920
result:
ok 1 number(s): "997920"
Test #4:
score: 0
Accepted
time: 124ms
memory: 159900kb
input:
100
output:
188898954
result:
ok 1 number(s): "188898954"
Test #5:
score: 0
Accepted
time: 125ms
memory: 159824kb
input:
4
output:
10
result:
ok 1 number(s): "10"
Test #6:
score: 0
Accepted
time: 117ms
memory: 159956kb
input:
8
output:
12336
result:
ok 1 number(s): "12336"
Test #7:
score: 0
Accepted
time: 129ms
memory: 159920kb
input:
16
output:
373118483
result:
ok 1 number(s): "373118483"
Test #8:
score: 0
Accepted
time: 125ms
memory: 159896kb
input:
32
output:
314585464
result:
ok 1 number(s): "314585464"
Test #9:
score: 0
Accepted
time: 135ms
memory: 159832kb
input:
64
output:
627827331
result:
ok 1 number(s): "627827331"
Test #10:
score: 0
Accepted
time: 122ms
memory: 159884kb
input:
128
output:
828497685
result:
ok 1 number(s): "828497685"
Test #11:
score: 0
Accepted
time: 120ms
memory: 159956kb
input:
256
output:
65697890
result:
ok 1 number(s): "65697890"
Test #12:
score: 0
Accepted
time: 116ms
memory: 159880kb
input:
512
output:
854187619
result:
ok 1 number(s): "854187619"
Test #13:
score: 0
Accepted
time: 100ms
memory: 159884kb
input:
1024
output:
513823539
result:
ok 1 number(s): "513823539"
Test #14:
score: 0
Accepted
time: 138ms
memory: 159892kb
input:
1361956
output:
617368199
result:
ok 1 number(s): "617368199"
Test #15:
score: -100
Wrong Answer
time: 194ms
memory: 159956kb
input:
7579013
output:
693151411
result:
wrong answer 1st numbers differ - expected: '827172636', found: '693151411'