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The 2nd Universal Cup Finals is coming! Check out our event page, schedule, and competition rules!
| ID | Problem | Submitter | Result | Time | Memory | Language | File size | Submit time | Judge time |
|---|---|---|---|---|---|---|---|---|---|
| #186210 | #6736. Alice and Bob | UrgantTeam# | AC ✓ | 103ms | 81576kb | C++23 | 1023b | 2023-09-23 13:21:05 | 2023-09-23 13:21:06 |
Judging History
answer
#include <bits/stdc++.h>
#define pb push_back
#define mp make_pair
#define x first
#define y second
using namespace std;
typedef long double ld;
typedef long long ll;
const int MOD = 998244353;
const int MAXN = (int) 1e7;
int fact[MAXN + 5], revfact[MAXN + 5];
int binpow(int x, int step)
{
int res = 1;
while (step > 0)
{
if (step & 1) res = (ll) res * x % MOD;
step /= 2;
x = (ll) x * x % MOD;
}
return res;
}
int main()
{
//freopen("input.txt", "r", stdin);
//freopen("output.txt", "w", stdout);
ios_base::sync_with_stdio(0); cin.tie(0);
int n;
cin >> n;
fact[0] = 1;
for (int i = 1; i <= n; i++) fact[i] = (ll) fact[i - 1] * i % MOD;
revfact[n] = binpow(fact[n], MOD - 2);
for (int i = n - 1; i >= 0; i--) revfact[i] = (ll) revfact[i + 1] * (i + 1) % MOD;
int ans = 0;
for (int k = 1; k <= (n + 1) / 2; k++) ans = (ans + (ll) fact[n - k] * fact[n - k] % MOD * revfact[n - 2 * k + 1]) % MOD;
cout << ans << '\n';
return 0;
}
Details
Tip: Click on the bar to expand more detailed information
Test #1:
score: 100
Accepted
time: 1ms
memory: 5484kb
input:
1
output:
1
result:
ok 1 number(s): "1"
Test #2:
score: 0
Accepted
time: 1ms
memory: 5492kb
input:
2
output:
1
result:
ok 1 number(s): "1"
Test #3:
score: 0
Accepted
time: 1ms
memory: 5476kb
input:
10
output:
997920
result:
ok 1 number(s): "997920"
Test #4:
score: 0
Accepted
time: 0ms
memory: 5420kb
input:
100
output:
188898954
result:
ok 1 number(s): "188898954"
Test #5:
score: 0
Accepted
time: 1ms
memory: 5572kb
input:
4
output:
10
result:
ok 1 number(s): "10"
Test #6:
score: 0
Accepted
time: 1ms
memory: 5496kb
input:
8
output:
12336
result:
ok 1 number(s): "12336"
Test #7:
score: 0
Accepted
time: 0ms
memory: 5492kb
input:
16
output:
373118483
result:
ok 1 number(s): "373118483"
Test #8:
score: 0
Accepted
time: 1ms
memory: 5508kb
input:
32
output:
314585464
result:
ok 1 number(s): "314585464"
Test #9:
score: 0
Accepted
time: 1ms
memory: 5640kb
input:
64
output:
627827331
result:
ok 1 number(s): "627827331"
Test #10:
score: 0
Accepted
time: 1ms
memory: 5500kb
input:
128
output:
828497685
result:
ok 1 number(s): "828497685"
Test #11:
score: 0
Accepted
time: 1ms
memory: 5500kb
input:
256
output:
65697890
result:
ok 1 number(s): "65697890"
Test #12:
score: 0
Accepted
time: 1ms
memory: 5424kb
input:
512
output:
854187619
result:
ok 1 number(s): "854187619"
Test #13:
score: 0
Accepted
time: 1ms
memory: 5652kb
input:
1024
output:
513823539
result:
ok 1 number(s): "513823539"
Test #14:
score: 0
Accepted
time: 16ms
memory: 15180kb
input:
1361956
output:
617368199
result:
ok 1 number(s): "617368199"
Test #15:
score: 0
Accepted
time: 71ms
memory: 64492kb
input:
7579013
output:
827172636
result:
ok 1 number(s): "827172636"
Test #16:
score: 0
Accepted
time: 86ms
memory: 68588kb
input:
8145517
output:
710624331
result:
ok 1 number(s): "710624331"
Test #17:
score: 0
Accepted
time: 67ms
memory: 54864kb
input:
6140463
output:
707600568
result:
ok 1 number(s): "707600568"
Test #18:
score: 0
Accepted
time: 38ms
memory: 35580kb
input:
3515281
output:
698302413
result:
ok 1 number(s): "698302413"
Test #19:
score: 0
Accepted
time: 68ms
memory: 63168kb
input:
6969586
output:
69470392
result:
ok 1 number(s): "69470392"
Test #20:
score: 0
Accepted
time: 30ms
memory: 27356kb
input:
2888636
output:
433579983
result:
ok 1 number(s): "433579983"
Test #21:
score: 0
Accepted
time: 103ms
memory: 81560kb
input:
9999998
output:
758172780
result:
ok 1 number(s): "758172780"
Test #22:
score: 0
Accepted
time: 98ms
memory: 81576kb
input:
9999999
output:
605195495
result:
ok 1 number(s): "605195495"
Test #23:
score: 0
Accepted
time: 102ms
memory: 81544kb
input:
10000000
output:
866813682
result:
ok 1 number(s): "866813682"