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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 BobQzong#AC ✓119ms82080kbC++14928b2024-10-11 14:23:332024-10-11 14:23:47

Judging History

你现在查看的是最新测评结果

  • [2024-10-11 14:23:47]
  • 评测
  • 测评结果:AC
  • 用时:119ms
  • 内存:82080kb
  • [2024-10-11 14:23:33]
  • 提交

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"