QOJ.ac
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 |
|---|---|---|---|---|---|---|---|---|---|
| #476734 | #6736. Alice and Bob | SinhoMoeme | AC ✓ | 102ms | 157856kb | C++23 | 563b | 2024-07-13 20:53:14 | 2024-07-13 20:53:15 |
Judging History
answer
#include<cstdio>
constexpr size_t MAX=(size_t)1e7;
constexpr long long MOD=998244353;
int n;
long long p[MAX],s[MAX],ans;
inline long long pow(long long x,long long k){
long long res=1;
while(k){
if(k&1) res=res*x%MOD;
x=(x*x)%MOD;
k>>=1;
}
return res;
}
int main(){
p[0]=1;
scanf("%d",&n);
for(int i=1;i<=n;++i) p[i]=p[i-1]*i%MOD;
s[n]=pow(p[n],MOD-2);
for(int i=n-1;i>=0;--i) s[i]=s[i+1]*(i+1)%MOD;
for(int i=1;i<=n+1>>1;++i){
ans+=p[n-i]*p[n-i]%MOD*s[n-(i<<1)+1]%MOD;
ans%=MOD;
}
printf("%lld",ans);
return 0;
}
详细
Test #1:
score: 100
Accepted
time: 0ms
memory: 3680kb
input:
1
output:
1
result:
ok 1 number(s): "1"
Test #2:
score: 0
Accepted
time: 0ms
memory: 3656kb
input:
2
output:
1
result:
ok 1 number(s): "1"
Test #3:
score: 0
Accepted
time: 0ms
memory: 3528kb
input:
10
output:
997920
result:
ok 1 number(s): "997920"
Test #4:
score: 0
Accepted
time: 0ms
memory: 3672kb
input:
100
output:
188898954
result:
ok 1 number(s): "188898954"
Test #5:
score: 0
Accepted
time: 0ms
memory: 3684kb
input:
4
output:
10
result:
ok 1 number(s): "10"
Test #6:
score: 0
Accepted
time: 0ms
memory: 3656kb
input:
8
output:
12336
result:
ok 1 number(s): "12336"
Test #7:
score: 0
Accepted
time: 0ms
memory: 3648kb
input:
16
output:
373118483
result:
ok 1 number(s): "373118483"
Test #8:
score: 0
Accepted
time: 0ms
memory: 3680kb
input:
32
output:
314585464
result:
ok 1 number(s): "314585464"
Test #9:
score: 0
Accepted
time: 0ms
memory: 3664kb
input:
64
output:
627827331
result:
ok 1 number(s): "627827331"
Test #10:
score: 0
Accepted
time: 0ms
memory: 3644kb
input:
128
output:
828497685
result:
ok 1 number(s): "828497685"
Test #11:
score: 0
Accepted
time: 0ms
memory: 3528kb
input:
256
output:
65697890
result:
ok 1 number(s): "65697890"
Test #12:
score: 0
Accepted
time: 0ms
memory: 3684kb
input:
512
output:
854187619
result:
ok 1 number(s): "854187619"
Test #13:
score: 0
Accepted
time: 0ms
memory: 3524kb
input:
1024
output:
513823539
result:
ok 1 number(s): "513823539"
Test #14:
score: 0
Accepted
time: 12ms
memory: 26416kb
input:
1361956
output:
617368199
result:
ok 1 number(s): "617368199"
Test #15:
score: 0
Accepted
time: 60ms
memory: 123048kb
input:
7579013
output:
827172636
result:
ok 1 number(s): "827172636"
Test #16:
score: 0
Accepted
time: 75ms
memory: 130776kb
input:
8145517
output:
710624331
result:
ok 1 number(s): "710624331"
Test #17:
score: 0
Accepted
time: 59ms
memory: 99204kb
input:
6140463
output:
707600568
result:
ok 1 number(s): "707600568"
Test #18:
score: 0
Accepted
time: 35ms
memory: 59860kb
input:
3515281
output:
698302413
result:
ok 1 number(s): "698302413"
Test #19:
score: 0
Accepted
time: 40ms
memory: 114740kb
input:
6969586
output:
69470392
result:
ok 1 number(s): "69470392"
Test #20:
score: 0
Accepted
time: 35ms
memory: 50272kb
input:
2888636
output:
433579983
result:
ok 1 number(s): "433579983"
Test #21:
score: 0
Accepted
time: 101ms
memory: 157856kb
input:
9999998
output:
758172780
result:
ok 1 number(s): "758172780"
Test #22:
score: 0
Accepted
time: 102ms
memory: 157856kb
input:
9999999
output:
605195495
result:
ok 1 number(s): "605195495"
Test #23:
score: 0
Accepted
time: 85ms
memory: 157836kb
input:
10000000
output:
866813682
result:
ok 1 number(s): "866813682"