QOJ.ac
QOJ
ID | Problem | Submitter | Result | Time | Memory | Language | File size | Submit time | Judge time |
---|---|---|---|---|---|---|---|---|---|
#183994 | #6736. Alice and Bob | supepapupu | AC ✓ | 111ms | 160088kb | C++17 | 1.3kb | 2023-09-20 09:42:55 | 2023-09-20 09:42:55 |
Judging History
answer
#include <bits/stdc++.h>
#define x first
#define y second
#define el '\n'
using namespace std;
typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
const int N = 1e7 + 10, INF = 0x3f3f3f3f, mod = 998244353;
inline int read() {
int f = 1, k = 0;
char c = getchar();
while (c < '0' || c > '9') {
if (c == '-') f = -1;
c = getchar();
}
while (c >= '0' && c <= '9') {
k = k * 10 + c - '0';
c = getchar();
}
return f * k;
}
ll qmi(ll a, ll b) {
ll res = 1;
while (b) {
if (b & 1) res = res * a % mod;
a = a * a % mod;
b >>= 1;
}
return res;
}
void add(ll &a, ll b) {
a += b;
if (a >= mod) a -= mod;
}
ll fact[N], invfact[N];
ll P(ll a, ll b) {
if (a < b) return 0;
return fact[a] * invfact[a - b] % mod;
}
int main() {
// ios::sync_with_stdio(0); cin.tie(0);
int n = read();
fact[0] = 1;
for (int i = 1; i <= n; ++i) fact[i] = fact[i - 1] * i % mod;
invfact[n] = qmi(fact[n], mod - 2);
for (int i = n; i; --i) invfact[i - 1] = invfact[i] * i % mod;
// if (n == 1) return puts("1"), 0;
ll ans = 0;
for (int i = 1; i <= n; ++i) {
add(ans, P(n - i, i - 1) * fact[n - i] % mod);
}
printf("%lld\n", ans);
}
Details
Tip: Click on the bar to expand more detailed information
Test #1:
score: 100
Accepted
time: 1ms
memory: 5996kb
input:
1
output:
1
result:
ok 1 number(s): "1"
Test #2:
score: 0
Accepted
time: 0ms
memory: 5804kb
input:
2
output:
1
result:
ok 1 number(s): "1"
Test #3:
score: 0
Accepted
time: 0ms
memory: 5868kb
input:
10
output:
997920
result:
ok 1 number(s): "997920"
Test #4:
score: 0
Accepted
time: 0ms
memory: 5888kb
input:
100
output:
188898954
result:
ok 1 number(s): "188898954"
Test #5:
score: 0
Accepted
time: 1ms
memory: 5864kb
input:
4
output:
10
result:
ok 1 number(s): "10"
Test #6:
score: 0
Accepted
time: 1ms
memory: 5932kb
input:
8
output:
12336
result:
ok 1 number(s): "12336"
Test #7:
score: 0
Accepted
time: 1ms
memory: 5804kb
input:
16
output:
373118483
result:
ok 1 number(s): "373118483"
Test #8:
score: 0
Accepted
time: 1ms
memory: 5880kb
input:
32
output:
314585464
result:
ok 1 number(s): "314585464"
Test #9:
score: 0
Accepted
time: 1ms
memory: 5808kb
input:
64
output:
627827331
result:
ok 1 number(s): "627827331"
Test #10:
score: 0
Accepted
time: 1ms
memory: 5892kb
input:
128
output:
828497685
result:
ok 1 number(s): "828497685"
Test #11:
score: 0
Accepted
time: 0ms
memory: 5876kb
input:
256
output:
65697890
result:
ok 1 number(s): "65697890"
Test #12:
score: 0
Accepted
time: 0ms
memory: 5892kb
input:
512
output:
854187619
result:
ok 1 number(s): "854187619"
Test #13:
score: 0
Accepted
time: 1ms
memory: 5916kb
input:
1024
output:
513823539
result:
ok 1 number(s): "513823539"
Test #14:
score: 0
Accepted
time: 14ms
memory: 28680kb
input:
1361956
output:
617368199
result:
ok 1 number(s): "617368199"
Test #15:
score: 0
Accepted
time: 77ms
memory: 126352kb
input:
7579013
output:
827172636
result:
ok 1 number(s): "827172636"
Test #16:
score: 0
Accepted
time: 85ms
memory: 134860kb
input:
8145517
output:
710624331
result:
ok 1 number(s): "710624331"
Test #17:
score: 0
Accepted
time: 32ms
memory: 103004kb
input:
6140463
output:
707600568
result:
ok 1 number(s): "707600568"
Test #18:
score: 0
Accepted
time: 32ms
memory: 60904kb
input:
3515281
output:
698302413
result:
ok 1 number(s): "698302413"
Test #19:
score: 0
Accepted
time: 74ms
memory: 114328kb
input:
6969586
output:
69470392
result:
ok 1 number(s): "69470392"
Test #20:
score: 0
Accepted
time: 12ms
memory: 52748kb
input:
2888636
output:
433579983
result:
ok 1 number(s): "433579983"
Test #21:
score: 0
Accepted
time: 111ms
memory: 160016kb
input:
9999998
output:
758172780
result:
ok 1 number(s): "758172780"
Test #22:
score: 0
Accepted
time: 69ms
memory: 160088kb
input:
9999999
output:
605195495
result:
ok 1 number(s): "605195495"
Test #23:
score: 0
Accepted
time: 94ms
memory: 160012kb
input:
10000000
output:
866813682
result:
ok 1 number(s): "866813682"