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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 |
---|---|---|---|---|---|---|---|---|---|
#629715 | #6736. Alice and Bob | Qzong# | AC ✓ | 119ms | 82080kb | C++14 | 928b | 2024-10-11 14:23:33 | 2024-10-11 14:23:47 |
Judging History
answer
#include <bits/stdc++.h>
int qpow(int a, int b, int p) {
int ans = 1;
for (; b; b >>= 1) {
if (b & 1) ans = 1ll * ans * a % p;
a = 1ll * a * a % p;
}
return ans;
}
const int N = 10001000;
const int mod = 998244353;
int n;
int fact[N], facv[N];
void fact_init(int n) {
fact[0] = 1;
for (int i = 1; i <= n; i ++) fact[i] = 1ll * fact[i - 1] * i % mod;
facv[n] = qpow(fact[n], mod - 2, mod);
for (int i = n - 1; i >= 0; i --) facv[i] = 1ll * facv[i + 1] * (i + 1) % mod;
}
int binom(int n, int m) {
if (n < m) return 0;
return 1ll * facv[m] * facv[n - m] % mod * fact[n] % mod;
}
int main() {
scanf("%d", &n);
fact_init(n);
int ans = fact[n - 1];
for (int x = 2; x <= n; x ++)
ans = (ans + 1ll * fact[x - 1] * fact[n - x] % mod * binom(n - x, x - 1)) % mod;
printf("%d\n", ans);
return 0;
}
详细
Test #1:
score: 100
Accepted
time: 1ms
memory: 5880kb
input:
1
output:
1
result:
ok 1 number(s): "1"
Test #2:
score: 0
Accepted
time: 1ms
memory: 5956kb
input:
2
output:
1
result:
ok 1 number(s): "1"
Test #3:
score: 0
Accepted
time: 1ms
memory: 5872kb
input:
10
output:
997920
result:
ok 1 number(s): "997920"
Test #4:
score: 0
Accepted
time: 1ms
memory: 5820kb
input:
100
output:
188898954
result:
ok 1 number(s): "188898954"
Test #5:
score: 0
Accepted
time: 1ms
memory: 5964kb
input:
4
output:
10
result:
ok 1 number(s): "10"
Test #6:
score: 0
Accepted
time: 1ms
memory: 5940kb
input:
8
output:
12336
result:
ok 1 number(s): "12336"
Test #7:
score: 0
Accepted
time: 1ms
memory: 5880kb
input:
16
output:
373118483
result:
ok 1 number(s): "373118483"
Test #8:
score: 0
Accepted
time: 1ms
memory: 5872kb
input:
32
output:
314585464
result:
ok 1 number(s): "314585464"
Test #9:
score: 0
Accepted
time: 1ms
memory: 5880kb
input:
64
output:
627827331
result:
ok 1 number(s): "627827331"
Test #10:
score: 0
Accepted
time: 0ms
memory: 5872kb
input:
128
output:
828497685
result:
ok 1 number(s): "828497685"
Test #11:
score: 0
Accepted
time: 0ms
memory: 5952kb
input:
256
output:
65697890
result:
ok 1 number(s): "65697890"
Test #12:
score: 0
Accepted
time: 1ms
memory: 5996kb
input:
512
output:
854187619
result:
ok 1 number(s): "854187619"
Test #13:
score: 0
Accepted
time: 1ms
memory: 5968kb
input:
1024
output:
513823539
result:
ok 1 number(s): "513823539"
Test #14:
score: 0
Accepted
time: 16ms
memory: 19156kb
input:
1361956
output:
617368199
result:
ok 1 number(s): "617368199"
Test #15:
score: 0
Accepted
time: 94ms
memory: 64876kb
input:
7579013
output:
827172636
result:
ok 1 number(s): "827172636"
Test #16:
score: 0
Accepted
time: 90ms
memory: 68936kb
input:
8145517
output:
710624331
result:
ok 1 number(s): "710624331"
Test #17:
score: 0
Accepted
time: 77ms
memory: 52944kb
input:
6140463
output:
707600568
result:
ok 1 number(s): "707600568"
Test #18:
score: 0
Accepted
time: 45ms
memory: 35256kb
input:
3515281
output:
698302413
result:
ok 1 number(s): "698302413"
Test #19:
score: 0
Accepted
time: 77ms
memory: 59980kb
input:
6969586
output:
69470392
result:
ok 1 number(s): "69470392"
Test #20:
score: 0
Accepted
time: 37ms
memory: 27880kb
input:
2888636
output:
433579983
result:
ok 1 number(s): "433579983"
Test #21:
score: 0
Accepted
time: 119ms
memory: 82032kb
input:
9999998
output:
758172780
result:
ok 1 number(s): "758172780"
Test #22:
score: 0
Accepted
time: 115ms
memory: 82080kb
input:
9999999
output:
605195495
result:
ok 1 number(s): "605195495"
Test #23:
score: 0
Accepted
time: 118ms
memory: 81900kb
input:
10000000
output:
866813682
result:
ok 1 number(s): "866813682"