QOJ.ac
QOJ
| ID | Problem | Submitter | Result | Time | Memory | Language | File size | Submit time | Judge time |
|---|---|---|---|---|---|---|---|---|---|
| #367845 | #6736. Alice and Bob | 1677118046# | WA | 85ms | 123408kb | C++17 | 1020b | 2024-03-26 15:19:07 | 2024-03-26 15:19:08 |
Judging History
answer
#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
const int nn=1e7+10;
ll dp[nn];
const ll mod=998244353;
ll pow1(ll bas,ll y){
ll ba=1;
while(y){
if(y&1){
ba*=bas;
ba%=mod;
}
y/=2;
bas*=bas;
bas%=mod;
}
return ba;
}
ll ji[nn];
ll inv[nn];
ll n;
void init(){
ji[0]=1;
for(ll i=1;i<=n;i++){
ji[i]=ji[i-1]*i;
ji[i]%=mod;
}
inv[n]=pow1(ji[n],mod-2);
for(ll i=n-1;i>=1;i--){
inv[i]=inv[i+1]*(i+1);
inv[i]%=mod;
}
}
void solve(){
cin>>n;
ll ans=0;
init();
if(n==1){
cout<<1<<"\n";return;
}
for(ll i=1;i<=(n+1)/2;i++){
ll an1=1;
/*
for(ll j=1;j<=i-1;j++){
an1*=(n-i-j+1);
}
*/
/*
for(int j=1;j<=n-i;j++){
an1*=j;
}
*/
ll pos1=n-i;
ll pos2=n-2*i+2;
an1 *= (ji[pos1] % mod * inv[pos2-1] % mod) % mod;
an1 %= mod;
an1*=ji[pos1];
an1%=mod;
ans+=an1;
ans%=mod;
}
cout<<ans<<"\n";
}
int main(){
ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
solve();
}
Details
Tip: Click on the bar to expand more detailed information
Test #1:
score: 100
Accepted
time: 1ms
memory: 5672kb
input:
1
output:
1
result:
ok 1 number(s): "1"
Test #2:
score: 0
Accepted
time: 1ms
memory: 5660kb
input:
2
output:
1
result:
ok 1 number(s): "1"
Test #3:
score: 0
Accepted
time: 0ms
memory: 5644kb
input:
10
output:
997920
result:
ok 1 number(s): "997920"
Test #4:
score: 0
Accepted
time: 1ms
memory: 5596kb
input:
100
output:
188898954
result:
ok 1 number(s): "188898954"
Test #5:
score: 0
Accepted
time: 1ms
memory: 5724kb
input:
4
output:
10
result:
ok 1 number(s): "10"
Test #6:
score: 0
Accepted
time: 0ms
memory: 5728kb
input:
8
output:
12336
result:
ok 1 number(s): "12336"
Test #7:
score: 0
Accepted
time: 1ms
memory: 5620kb
input:
16
output:
373118483
result:
ok 1 number(s): "373118483"
Test #8:
score: 0
Accepted
time: 1ms
memory: 5672kb
input:
32
output:
314585464
result:
ok 1 number(s): "314585464"
Test #9:
score: 0
Accepted
time: 1ms
memory: 5728kb
input:
64
output:
627827331
result:
ok 1 number(s): "627827331"
Test #10:
score: 0
Accepted
time: 1ms
memory: 5620kb
input:
128
output:
828497685
result:
ok 1 number(s): "828497685"
Test #11:
score: 0
Accepted
time: 0ms
memory: 5616kb
input:
256
output:
65697890
result:
ok 1 number(s): "65697890"
Test #12:
score: 0
Accepted
time: 1ms
memory: 5732kb
input:
512
output:
854187619
result:
ok 1 number(s): "854187619"
Test #13:
score: 0
Accepted
time: 1ms
memory: 5716kb
input:
1024
output:
513823539
result:
ok 1 number(s): "513823539"
Test #14:
score: 0
Accepted
time: 14ms
memory: 26800kb
input:
1361956
output:
617368199
result:
ok 1 number(s): "617368199"
Test #15:
score: -100
Wrong Answer
time: 85ms
memory: 123408kb
input:
7579013
output:
693151411
result:
wrong answer 1st numbers differ - expected: '827172636', found: '693151411'