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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 |
---|---|---|---|---|---|---|---|---|---|
#760018 | #6736. Alice and Bob | ship2077 | AC ✓ | 109ms | 81956kb | C++23 | 696b | 2024-11-18 14:06:45 | 2024-11-18 14:06:49 |
Judging History
answer
#include<bits/stdc++.h>
using namespace std;
constexpr int M=1e7+5,mod=998244353;
int n,ans,fac[M],ifac[M];
int read(){
int x=0;char ch=getchar();
while (!isdigit(ch)) ch=getchar();
while (isdigit(ch)) x=x*10+ch-48,ch=getchar();
return x;
}
int qpow(int x,int n){
int s=1; while (n){
if (n&1) s=1ll*s*x%mod;
x=1ll*x*x%mod; n>>=1;
} return s;
}
void init(int n){
for (int i=fac[0]=1;i<=n;i++) fac[i]=1ll*fac[i-1]*i%mod;
ifac[n]=qpow(fac[n],mod-2);
for (int i=n;i;i--) ifac[i-1]=1ll*ifac[i]*i%mod;
}
int main(){
n=read();init(n);
for (int i=1;(i<<1)-1<=n;i++)
ans=(ans+1ll*fac[n-i]*ifac[n-(i<<1)+1]%mod*fac[n-i])%mod;
printf("%d\n",ans);
return 0;
}
详细
Test #1:
score: 100
Accepted
time: 1ms
memory: 5824kb
input:
1
output:
1
result:
ok 1 number(s): "1"
Test #2:
score: 0
Accepted
time: 1ms
memory: 5772kb
input:
2
output:
1
result:
ok 1 number(s): "1"
Test #3:
score: 0
Accepted
time: 1ms
memory: 5820kb
input:
10
output:
997920
result:
ok 1 number(s): "997920"
Test #4:
score: 0
Accepted
time: 1ms
memory: 5808kb
input:
100
output:
188898954
result:
ok 1 number(s): "188898954"
Test #5:
score: 0
Accepted
time: 1ms
memory: 5840kb
input:
4
output:
10
result:
ok 1 number(s): "10"
Test #6:
score: 0
Accepted
time: 1ms
memory: 5768kb
input:
8
output:
12336
result:
ok 1 number(s): "12336"
Test #7:
score: 0
Accepted
time: 0ms
memory: 5756kb
input:
16
output:
373118483
result:
ok 1 number(s): "373118483"
Test #8:
score: 0
Accepted
time: 0ms
memory: 5820kb
input:
32
output:
314585464
result:
ok 1 number(s): "314585464"
Test #9:
score: 0
Accepted
time: 0ms
memory: 5820kb
input:
64
output:
627827331
result:
ok 1 number(s): "627827331"
Test #10:
score: 0
Accepted
time: 0ms
memory: 5896kb
input:
128
output:
828497685
result:
ok 1 number(s): "828497685"
Test #11:
score: 0
Accepted
time: 0ms
memory: 5832kb
input:
256
output:
65697890
result:
ok 1 number(s): "65697890"
Test #12:
score: 0
Accepted
time: 0ms
memory: 5824kb
input:
512
output:
854187619
result:
ok 1 number(s): "854187619"
Test #13:
score: 0
Accepted
time: 1ms
memory: 5840kb
input:
1024
output:
513823539
result:
ok 1 number(s): "513823539"
Test #14:
score: 0
Accepted
time: 13ms
memory: 15640kb
input:
1361956
output:
617368199
result:
ok 1 number(s): "617368199"
Test #15:
score: 0
Accepted
time: 89ms
memory: 64984kb
input:
7579013
output:
827172636
result:
ok 1 number(s): "827172636"
Test #16:
score: 0
Accepted
time: 83ms
memory: 69248kb
input:
8145517
output:
710624331
result:
ok 1 number(s): "710624331"
Test #17:
score: 0
Accepted
time: 72ms
memory: 52724kb
input:
6140463
output:
707600568
result:
ok 1 number(s): "707600568"
Test #18:
score: 0
Accepted
time: 38ms
memory: 35876kb
input:
3515281
output:
698302413
result:
ok 1 number(s): "698302413"
Test #19:
score: 0
Accepted
time: 69ms
memory: 61272kb
input:
6969586
output:
69470392
result:
ok 1 number(s): "69470392"
Test #20:
score: 0
Accepted
time: 34ms
memory: 27708kb
input:
2888636
output:
433579983
result:
ok 1 number(s): "433579983"
Test #21:
score: 0
Accepted
time: 93ms
memory: 81904kb
input:
9999998
output:
758172780
result:
ok 1 number(s): "758172780"
Test #22:
score: 0
Accepted
time: 109ms
memory: 81816kb
input:
9999999
output:
605195495
result:
ok 1 number(s): "605195495"
Test #23:
score: 0
Accepted
time: 101ms
memory: 81956kb
input:
10000000
output:
866813682
result:
ok 1 number(s): "866813682"