QOJ.ac
QOJ
| ID | Problem | Submitter | Result | Time | Memory | Language | File size | Submit time | Judge time |
|---|---|---|---|---|---|---|---|---|---|
| #387327 | #6736. Alice and Bob | k1nsom | AC ✓ | 206ms | 159988kb | C++17 | 1.0kb | 2024-04-12 13:35:58 | 2024-04-12 13:35:59 |
Judging History
answer
#include <bits/stdc++.h>
using namespace std;
#define int long long
#define N 10000005
#define endl '\n'
#define mod 998244353
int n, ans, col, jc[N + 5] = {0}, inv[N + 5] = {0};
void init()
{
jc[0] = 1;
for (int i = 1; i <= N; i++)
jc[i] = (i * jc[i - 1]) % mod;
inv[1] = 1;
for (int i = 2; i <= N; i++)
inv[i] = (mod - mod / i) * inv[mod % i] % mod;
}
signed main()
{
cin >> n;
col = 1;
init();
col = 1;
for (int i = 1; 2 * i <= n + 1; i++)
{
if (i - 1 == 0 || n + 1 == 2 * i)
ans = (ans + jc[i - 1] * jc[n - i] % mod) % mod;
else
{
if (i == 2)
col = (col * (n - i)) % mod;
else
col = (col * inv[n - i + 1] % mod * inv[i - 1] % mod * (n - 2 * i + 3) % mod * (n - 2 * i + 2)) % mod;
ans = (ans + col * jc[i - 1] % mod * jc[n - i] % mod) % mod; // col(n - i, i - 1)
}
// cout << col << endl;
}
cout << ans << endl;
return 0;
}
Details
Tip: Click on the bar to expand more detailed information
Test #1:
score: 100
Accepted
time: 111ms
memory: 159964kb
input:
1
output:
1
result:
ok 1 number(s): "1"
Test #2:
score: 0
Accepted
time: 101ms
memory: 159836kb
input:
2
output:
1
result:
ok 1 number(s): "1"
Test #3:
score: 0
Accepted
time: 105ms
memory: 159964kb
input:
10
output:
997920
result:
ok 1 number(s): "997920"
Test #4:
score: 0
Accepted
time: 106ms
memory: 159832kb
input:
100
output:
188898954
result:
ok 1 number(s): "188898954"
Test #5:
score: 0
Accepted
time: 101ms
memory: 159832kb
input:
4
output:
10
result:
ok 1 number(s): "10"
Test #6:
score: 0
Accepted
time: 128ms
memory: 159964kb
input:
8
output:
12336
result:
ok 1 number(s): "12336"
Test #7:
score: 0
Accepted
time: 99ms
memory: 159904kb
input:
16
output:
373118483
result:
ok 1 number(s): "373118483"
Test #8:
score: 0
Accepted
time: 119ms
memory: 159900kb
input:
32
output:
314585464
result:
ok 1 number(s): "314585464"
Test #9:
score: 0
Accepted
time: 121ms
memory: 159840kb
input:
64
output:
627827331
result:
ok 1 number(s): "627827331"
Test #10:
score: 0
Accepted
time: 115ms
memory: 159900kb
input:
128
output:
828497685
result:
ok 1 number(s): "828497685"
Test #11:
score: 0
Accepted
time: 115ms
memory: 159900kb
input:
256
output:
65697890
result:
ok 1 number(s): "65697890"
Test #12:
score: 0
Accepted
time: 88ms
memory: 159776kb
input:
512
output:
854187619
result:
ok 1 number(s): "854187619"
Test #13:
score: 0
Accepted
time: 120ms
memory: 159836kb
input:
1024
output:
513823539
result:
ok 1 number(s): "513823539"
Test #14:
score: 0
Accepted
time: 117ms
memory: 159900kb
input:
1361956
output:
617368199
result:
ok 1 number(s): "617368199"
Test #15:
score: 0
Accepted
time: 170ms
memory: 159840kb
input:
7579013
output:
827172636
result:
ok 1 number(s): "827172636"
Test #16:
score: 0
Accepted
time: 162ms
memory: 159900kb
input:
8145517
output:
710624331
result:
ok 1 number(s): "710624331"
Test #17:
score: 0
Accepted
time: 150ms
memory: 159988kb
input:
6140463
output:
707600568
result:
ok 1 number(s): "707600568"
Test #18:
score: 0
Accepted
time: 126ms
memory: 159916kb
input:
3515281
output:
698302413
result:
ok 1 number(s): "698302413"
Test #19:
score: 0
Accepted
time: 160ms
memory: 159908kb
input:
6969586
output:
69470392
result:
ok 1 number(s): "69470392"
Test #20:
score: 0
Accepted
time: 128ms
memory: 159836kb
input:
2888636
output:
433579983
result:
ok 1 number(s): "433579983"
Test #21:
score: 0
Accepted
time: 170ms
memory: 159964kb
input:
9999998
output:
758172780
result:
ok 1 number(s): "758172780"
Test #22:
score: 0
Accepted
time: 206ms
memory: 159836kb
input:
9999999
output:
605195495
result:
ok 1 number(s): "605195495"
Test #23:
score: 0
Accepted
time: 205ms
memory: 159908kb
input:
10000000
output:
866813682
result:
ok 1 number(s): "866813682"