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 |
|---|---|---|---|---|---|---|---|---|---|
| #404961 | #6736. Alice and Bob | qzuser | AC ✓ | 605ms | 81696kb | C++17 | 672b | 2024-05-05 03:55:05 | 2024-05-05 03:55:06 |
Judging History
answer
#include<bits/stdc++.h>
using namespace std;
#define int long long
const int mod = 998244353;
const int N = 1e7 + 10;
int f[N];
int qmi(int a, int b)
{
int res = 1;
while (b)
{
if (b & 1) res = res * a % mod;
a = a * a % mod;
b >>= 1;
}
return res;
}
signed main()
{
int n;
cin >> n;
f[0] = 1;
for (int i = 1; i <= n; i ++) f[i] = f[i - 1] * i % mod;
int ans = 0;
for (int i = 1; i <= n; i ++)
{
if (n - i >= i - 1)
ans = (ans + f[n - i] * f[n - i] % mod * qmi(f[n - 2 * i + 1], mod - 2) % mod) % mod;
}
cout << ans << endl;
return 0;
}
详细
Test #1:
score: 100
Accepted
time: 0ms
memory: 3572kb
input:
1
output:
1
result:
ok 1 number(s): "1"
Test #2:
score: 0
Accepted
time: 1ms
memory: 3636kb
input:
2
output:
1
result:
ok 1 number(s): "1"
Test #3:
score: 0
Accepted
time: 1ms
memory: 3444kb
input:
10
output:
997920
result:
ok 1 number(s): "997920"
Test #4:
score: 0
Accepted
time: 0ms
memory: 3448kb
input:
100
output:
188898954
result:
ok 1 number(s): "188898954"
Test #5:
score: 0
Accepted
time: 0ms
memory: 3576kb
input:
4
output:
10
result:
ok 1 number(s): "10"
Test #6:
score: 0
Accepted
time: 0ms
memory: 3496kb
input:
8
output:
12336
result:
ok 1 number(s): "12336"
Test #7:
score: 0
Accepted
time: 0ms
memory: 3660kb
input:
16
output:
373118483
result:
ok 1 number(s): "373118483"
Test #8:
score: 0
Accepted
time: 0ms
memory: 3564kb
input:
32
output:
314585464
result:
ok 1 number(s): "314585464"
Test #9:
score: 0
Accepted
time: 0ms
memory: 3464kb
input:
64
output:
627827331
result:
ok 1 number(s): "627827331"
Test #10:
score: 0
Accepted
time: 0ms
memory: 3452kb
input:
128
output:
828497685
result:
ok 1 number(s): "828497685"
Test #11:
score: 0
Accepted
time: 0ms
memory: 3636kb
input:
256
output:
65697890
result:
ok 1 number(s): "65697890"
Test #12:
score: 0
Accepted
time: 1ms
memory: 3592kb
input:
512
output:
854187619
result:
ok 1 number(s): "854187619"
Test #13:
score: 0
Accepted
time: 0ms
memory: 3576kb
input:
1024
output:
513823539
result:
ok 1 number(s): "513823539"
Test #14:
score: 0
Accepted
time: 73ms
memory: 16144kb
input:
1361956
output:
617368199
result:
ok 1 number(s): "617368199"
Test #15:
score: 0
Accepted
time: 460ms
memory: 64404kb
input:
7579013
output:
827172636
result:
ok 1 number(s): "827172636"
Test #16:
score: 0
Accepted
time: 491ms
memory: 67236kb
input:
8145517
output:
710624331
result:
ok 1 number(s): "710624331"
Test #17:
score: 0
Accepted
time: 371ms
memory: 53168kb
input:
6140463
output:
707600568
result:
ok 1 number(s): "707600568"
Test #18:
score: 0
Accepted
time: 217ms
memory: 32676kb
input:
3515281
output:
698302413
result:
ok 1 number(s): "698302413"
Test #19:
score: 0
Accepted
time: 418ms
memory: 58892kb
input:
6969586
output:
69470392
result:
ok 1 number(s): "69470392"
Test #20:
score: 0
Accepted
time: 179ms
memory: 28100kb
input:
2888636
output:
433579983
result:
ok 1 number(s): "433579983"
Test #21:
score: 0
Accepted
time: 597ms
memory: 81692kb
input:
9999998
output:
758172780
result:
ok 1 number(s): "758172780"
Test #22:
score: 0
Accepted
time: 605ms
memory: 81696kb
input:
9999999
output:
605195495
result:
ok 1 number(s): "605195495"
Test #23:
score: 0
Accepted
time: 601ms
memory: 81672kb
input:
10000000
output:
866813682
result:
ok 1 number(s): "866813682"