QOJ.ac
QOJ
ID | Problem | Submitter | Result | Time | Memory | Language | File size | Submit time | Judge time |
---|---|---|---|---|---|---|---|---|---|
#412554 | #6736. Alice and Bob | Sunlight9# | AC ✓ | 211ms | 159872kb | C++20 | 774b | 2024-05-16 16:04:26 | 2024-05-16 16:04:26 |
Judging History
answer
#include <bits/stdc++.h>
#define ll long long
using namespace std;
const int MAXN=1e7+7;
ll mod=998244353LL;
ll sum[MAXN],inv[MAXN];
int n;
inline ll ksm(ll x,ll y)
{
ll res=1LL;
while(y)
{
if(y&1LL) res=(res*x)%mod;
x=(x*x)%mod;y=y>>1LL;
}
return res;
}
inline ll A(int x,int y)
{
if(y>x) return 0;
ll res=sum[x]*inv[x-y];
return res%mod;
}
int main()
{
cin>>n;
sum[0]=1LL;
for(int i=1;i<=n;i++) sum[i]=(sum[i-1]*(ll) i)%mod;
inv[n]=ksm(sum[n],mod-2LL);
for(int i=n-1;i>=1;i--) inv[i]=(inv[i+1]*(ll) (i+1LL))%mod;
inv[0]=1LL;
ll ans=0LL;
for(int i=1;i<=n;i++)
{
ans+=A(n-i,i-1)*sum[n-i];
ans%=mod;
}
cout<<ans;
return 0;
}
Details
Tip: Click on the bar to expand more detailed information
Test #1:
score: 100
Accepted
time: 1ms
memory: 5732kb
input:
1
output:
1
result:
ok 1 number(s): "1"
Test #2:
score: 0
Accepted
time: 1ms
memory: 5668kb
input:
2
output:
1
result:
ok 1 number(s): "1"
Test #3:
score: 0
Accepted
time: 1ms
memory: 5644kb
input:
10
output:
997920
result:
ok 1 number(s): "997920"
Test #4:
score: 0
Accepted
time: 1ms
memory: 5536kb
input:
100
output:
188898954
result:
ok 1 number(s): "188898954"
Test #5:
score: 0
Accepted
time: 1ms
memory: 5732kb
input:
4
output:
10
result:
ok 1 number(s): "10"
Test #6:
score: 0
Accepted
time: 1ms
memory: 5576kb
input:
8
output:
12336
result:
ok 1 number(s): "12336"
Test #7:
score: 0
Accepted
time: 1ms
memory: 5724kb
input:
16
output:
373118483
result:
ok 1 number(s): "373118483"
Test #8:
score: 0
Accepted
time: 1ms
memory: 5572kb
input:
32
output:
314585464
result:
ok 1 number(s): "314585464"
Test #9:
score: 0
Accepted
time: 1ms
memory: 5576kb
input:
64
output:
627827331
result:
ok 1 number(s): "627827331"
Test #10:
score: 0
Accepted
time: 1ms
memory: 5664kb
input:
128
output:
828497685
result:
ok 1 number(s): "828497685"
Test #11:
score: 0
Accepted
time: 1ms
memory: 5576kb
input:
256
output:
65697890
result:
ok 1 number(s): "65697890"
Test #12:
score: 0
Accepted
time: 1ms
memory: 5596kb
input:
512
output:
854187619
result:
ok 1 number(s): "854187619"
Test #13:
score: 0
Accepted
time: 1ms
memory: 5732kb
input:
1024
output:
513823539
result:
ok 1 number(s): "513823539"
Test #14:
score: 0
Accepted
time: 21ms
memory: 27116kb
input:
1361956
output:
617368199
result:
ok 1 number(s): "617368199"
Test #15:
score: 0
Accepted
time: 147ms
memory: 122600kb
input:
7579013
output:
827172636
result:
ok 1 number(s): "827172636"
Test #16:
score: 0
Accepted
time: 124ms
memory: 133864kb
input:
8145517
output:
710624331
result:
ok 1 number(s): "710624331"
Test #17:
score: 0
Accepted
time: 103ms
memory: 101420kb
input:
6140463
output:
707600568
result:
ok 1 number(s): "707600568"
Test #18:
score: 0
Accepted
time: 71ms
memory: 60176kb
input:
3515281
output:
698302413
result:
ok 1 number(s): "698302413"
Test #19:
score: 0
Accepted
time: 140ms
memory: 113752kb
input:
6969586
output:
69470392
result:
ok 1 number(s): "69470392"
Test #20:
score: 0
Accepted
time: 62ms
memory: 52156kb
input:
2888636
output:
433579983
result:
ok 1 number(s): "433579983"
Test #21:
score: 0
Accepted
time: 211ms
memory: 159840kb
input:
9999998
output:
758172780
result:
ok 1 number(s): "758172780"
Test #22:
score: 0
Accepted
time: 210ms
memory: 159776kb
input:
9999999
output:
605195495
result:
ok 1 number(s): "605195495"
Test #23:
score: 0
Accepted
time: 206ms
memory: 159872kb
input:
10000000
output:
866813682
result:
ok 1 number(s): "866813682"