QOJ.ac
QOJ
| ID | Problem | Submitter | Result | Time | Memory | Language | File size | Submit time | Judge time |
|---|---|---|---|---|---|---|---|---|---|
| #185403 | #6736. Alice and Bob | ucup-team134# | AC ✓ | 160ms | 82072kb | C++14 | 754b | 2023-09-22 01:00:42 | 2023-09-22 01:00:42 |
Judging History
answer
#include <bits/stdc++.h>
using namespace std;
#define ll long long
const int mod=998244353;
int mul(int x,int y){return (ll)x*y%mod;}
int add(int x,int y){x+=y;return x>=mod?x-mod:x;}
int sub(int x,int y){x-=y;return x<0?x+mod:x;}
const int N=10000050;
int F[N],I[N];
int binom(int n,int k){
return mul(F[n],mul(I[k],I[n-k]));
}
int main(){
int n;
scanf("%i",&n);
F[0]=1;
for(int i=1;i<=n;i++)F[i]=mul(F[i-1],i);
I[0]=I[1]=1;
for(int i=2;i<=n;i++)I[i]=mul(mod-mod/i,I[mod%i]);
for(int i=2;i<=n;i++)I[i]=mul(I[i-1],I[i]);
int ans=0;
for(int fir=1;fir<=n;fir++){
int hi=n-fir;
int need=fir-1;
if(hi>=need){
ans=add(ans,mul(binom(hi,need),mul(F[need],F[n-fir])));
}
}
printf("%i\n",ans);
return 0;
}
Details
Tip: Click on the bar to expand more detailed information
Test #1:
score: 100
Accepted
time: 1ms
memory: 5988kb
input:
1
output:
1
result:
ok 1 number(s): "1"
Test #2:
score: 0
Accepted
time: 0ms
memory: 5992kb
input:
2
output:
1
result:
ok 1 number(s): "1"
Test #3:
score: 0
Accepted
time: 1ms
memory: 5836kb
input:
10
output:
997920
result:
ok 1 number(s): "997920"
Test #4:
score: 0
Accepted
time: 1ms
memory: 5908kb
input:
100
output:
188898954
result:
ok 1 number(s): "188898954"
Test #5:
score: 0
Accepted
time: 1ms
memory: 5908kb
input:
4
output:
10
result:
ok 1 number(s): "10"
Test #6:
score: 0
Accepted
time: 1ms
memory: 5992kb
input:
8
output:
12336
result:
ok 1 number(s): "12336"
Test #7:
score: 0
Accepted
time: 1ms
memory: 5916kb
input:
16
output:
373118483
result:
ok 1 number(s): "373118483"
Test #8:
score: 0
Accepted
time: 1ms
memory: 5920kb
input:
32
output:
314585464
result:
ok 1 number(s): "314585464"
Test #9:
score: 0
Accepted
time: 0ms
memory: 5840kb
input:
64
output:
627827331
result:
ok 1 number(s): "627827331"
Test #10:
score: 0
Accepted
time: 1ms
memory: 5992kb
input:
128
output:
828497685
result:
ok 1 number(s): "828497685"
Test #11:
score: 0
Accepted
time: 1ms
memory: 5996kb
input:
256
output:
65697890
result:
ok 1 number(s): "65697890"
Test #12:
score: 0
Accepted
time: 0ms
memory: 5916kb
input:
512
output:
854187619
result:
ok 1 number(s): "854187619"
Test #13:
score: 0
Accepted
time: 0ms
memory: 5880kb
input:
1024
output:
513823539
result:
ok 1 number(s): "513823539"
Test #14:
score: 0
Accepted
time: 24ms
memory: 15584kb
input:
1361956
output:
617368199
result:
ok 1 number(s): "617368199"
Test #15:
score: 0
Accepted
time: 116ms
memory: 65500kb
input:
7579013
output:
827172636
result:
ok 1 number(s): "827172636"
Test #16:
score: 0
Accepted
time: 127ms
memory: 72096kb
input:
8145517
output:
710624331
result:
ok 1 number(s): "710624331"
Test #17:
score: 0
Accepted
time: 87ms
memory: 56424kb
input:
6140463
output:
707600568
result:
ok 1 number(s): "707600568"
Test #18:
score: 0
Accepted
time: 55ms
memory: 35332kb
input:
3515281
output:
698302413
result:
ok 1 number(s): "698302413"
Test #19:
score: 0
Accepted
time: 107ms
memory: 61120kb
input:
6969586
output:
69470392
result:
ok 1 number(s): "69470392"
Test #20:
score: 0
Accepted
time: 41ms
memory: 30968kb
input:
2888636
output:
433579983
result:
ok 1 number(s): "433579983"
Test #21:
score: 0
Accepted
time: 158ms
memory: 81928kb
input:
9999998
output:
758172780
result:
ok 1 number(s): "758172780"
Test #22:
score: 0
Accepted
time: 160ms
memory: 82072kb
input:
9999999
output:
605195495
result:
ok 1 number(s): "605195495"
Test #23:
score: 0
Accepted
time: 147ms
memory: 81996kb
input:
10000000
output:
866813682
result:
ok 1 number(s): "866813682"