QOJ.ac
QOJ
ID | Problem | Submitter | Result | Time | Memory | Language | File size | Submit time | Judge time |
---|---|---|---|---|---|---|---|---|---|
#335233 | #6736. Alice and Bob | ucup-team1198# | AC ✓ | 95ms | 81816kb | C++17 | 1.3kb | 2024-02-22 22:58:42 | 2024-02-22 22:58:42 |
Judging History
answer
#include <map>
#include <set>
#include <array>
#include <cmath>
#include <deque>
#include <bitset>
#include <random>
#include <string>
#include <vector>
#include <cassert>
#include <complex>
#include <iomanip>
#include <iostream>
#include <algorithm>
#include <unordered_map>
#include <unordered_set>
using namespace std;
const int MOD = 998244353;
int add(int a, int b) {
return a + b >= MOD ? a + b - MOD : a + b;
}
int sub(int a, int b) {
return a >= b ? a - b : a + MOD - b;
}
int mul(int a, int b) {
return (1ll * a * b) % MOD;
}
int pw(int x, int n) {
int res = 1;
while (n) {
if (n % 2 == 0) {
x = mul(x, x);
n /= 2;
} else {
res = mul(res, x);
--n;
}
}
return res;
}
const int MAXN = 10'000'010;
int facts[MAXN];
int anti_facts[MAXN];
int main() {
ios::sync_with_stdio(false);
cin.tie(0);
cout.tie(0);
facts[0] = 1;
for (int i = 1; i < MAXN; ++i)
facts[i] = mul(facts[i - 1], i);
anti_facts[MAXN - 1] = pw(facts[MAXN - 1], MOD - 2);
for (int i = MAXN - 2; i >= 0; --i)
anti_facts[i] = mul(anti_facts[i + 1], i + 1);
int n;
cin >> n;
int ans = 0;
for (int x = 1; 2 * x <= n + 1; ++x) {
ans = add(ans, mul(mul(facts[n - x], facts[n - x]), anti_facts[n - 2 * x + 1]));
}
cout << ans << '\n';
return 0;
}
Details
Tip: Click on the bar to expand more detailed information
Test #1:
score: 100
Accepted
time: 84ms
memory: 81620kb
input:
1
output:
1
result:
ok 1 number(s): "1"
Test #2:
score: 0
Accepted
time: 83ms
memory: 81668kb
input:
2
output:
1
result:
ok 1 number(s): "1"
Test #3:
score: 0
Accepted
time: 82ms
memory: 81680kb
input:
10
output:
997920
result:
ok 1 number(s): "997920"
Test #4:
score: 0
Accepted
time: 83ms
memory: 81748kb
input:
100
output:
188898954
result:
ok 1 number(s): "188898954"
Test #5:
score: 0
Accepted
time: 83ms
memory: 81676kb
input:
4
output:
10
result:
ok 1 number(s): "10"
Test #6:
score: 0
Accepted
time: 87ms
memory: 81764kb
input:
8
output:
12336
result:
ok 1 number(s): "12336"
Test #7:
score: 0
Accepted
time: 83ms
memory: 81812kb
input:
16
output:
373118483
result:
ok 1 number(s): "373118483"
Test #8:
score: 0
Accepted
time: 71ms
memory: 81740kb
input:
32
output:
314585464
result:
ok 1 number(s): "314585464"
Test #9:
score: 0
Accepted
time: 76ms
memory: 81716kb
input:
64
output:
627827331
result:
ok 1 number(s): "627827331"
Test #10:
score: 0
Accepted
time: 82ms
memory: 81760kb
input:
128
output:
828497685
result:
ok 1 number(s): "828497685"
Test #11:
score: 0
Accepted
time: 87ms
memory: 81804kb
input:
256
output:
65697890
result:
ok 1 number(s): "65697890"
Test #12:
score: 0
Accepted
time: 75ms
memory: 81684kb
input:
512
output:
854187619
result:
ok 1 number(s): "854187619"
Test #13:
score: 0
Accepted
time: 79ms
memory: 81764kb
input:
1024
output:
513823539
result:
ok 1 number(s): "513823539"
Test #14:
score: 0
Accepted
time: 84ms
memory: 81724kb
input:
1361956
output:
617368199
result:
ok 1 number(s): "617368199"
Test #15:
score: 0
Accepted
time: 88ms
memory: 81752kb
input:
7579013
output:
827172636
result:
ok 1 number(s): "827172636"
Test #16:
score: 0
Accepted
time: 86ms
memory: 81816kb
input:
8145517
output:
710624331
result:
ok 1 number(s): "710624331"
Test #17:
score: 0
Accepted
time: 91ms
memory: 81764kb
input:
6140463
output:
707600568
result:
ok 1 number(s): "707600568"
Test #18:
score: 0
Accepted
time: 83ms
memory: 81652kb
input:
3515281
output:
698302413
result:
ok 1 number(s): "698302413"
Test #19:
score: 0
Accepted
time: 92ms
memory: 81684kb
input:
6969586
output:
69470392
result:
ok 1 number(s): "69470392"
Test #20:
score: 0
Accepted
time: 83ms
memory: 81760kb
input:
2888636
output:
433579983
result:
ok 1 number(s): "433579983"
Test #21:
score: 0
Accepted
time: 95ms
memory: 81668kb
input:
9999998
output:
758172780
result:
ok 1 number(s): "758172780"
Test #22:
score: 0
Accepted
time: 84ms
memory: 81740kb
input:
9999999
output:
605195495
result:
ok 1 number(s): "605195495"
Test #23:
score: 0
Accepted
time: 95ms
memory: 81672kb
input:
10000000
output:
866813682
result:
ok 1 number(s): "866813682"