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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
#413443#6736. Alice and BobHHY_zZhu#AC ✓104ms159336kbC++141.9kb2024-05-17 16:01:102024-05-17 16:01:12

Judging History

你现在查看的是最新测评结果

  • [2024-05-17 16:01:12]
  • 评测
  • 测评结果:AC
  • 用时:104ms
  • 内存:159336kb
  • [2024-05-17 16:01:10]
  • 提交

answer

template<class T,class T2> int chkmn(T &a,T2 b){return a>b?a=b,1:0;}
template<class T,class T2> int chkmx(T &a,T2 b){return a<b?a=b,1:0;}
#include <bits/stdc++.h>
using namespace std;
#define V vector
#define all0(x) (x).begin(),(x).end()
#define all1(x) (x).begin()+1,(x).end()
#define pb push_back
#define eb emplace_back
#define fi first
#define se second
#define lb lower_bound
#define ub upper_bound
#define cin std::cin
#define cout std::cout
typedef long long LL;
typedef pair<int, int> pi;
typedef pair<LL, LL> pl;
#ifdef LOCAL
#include "C:/Users/lijia/Desktop/vscode/algo/debug.h"
#else
#define debug(...) 42
#endif

//const int MN = 2e5 + 20;//MaxN 记得改一下
const int INF = 2e9+1000;//INF
const LL INFLL = 8e18+1000;//INF long long 
mt19937 mrand(random_device{}());
//模板区域~~~~~~~

//模板结束~~~~~~~
const int mod = 998244353;
LL qpow(int x, LL k) {
    LL ans = 1;
    while(k) {
        if(k & 1) ans = ans * x % mod;
        x = 1LL * x * x % mod;
        k /= 2;
    }
    return ans;
}
LL inv(int x) {
    return qpow(x, mod - 2);
}
void solve() {
    int n; cin >> n;
    V<LL> fac(n + 1);
    V<LL> ifac(n + 1);
    fac[0] = 1;
    for(int i = 1; i <= n; i++) fac[i] = fac[i - 1] * i % mod;
    ifac[n] = inv(fac[n]);
    for(int i = n - 1; i >= 0; i--) {
        ifac[i] = ifac[i + 1] * (i + 1) % mod;
    }
    auto A = [&](int x, int k) -> LL {
        if(k > x || k < 0) return 0;
        return fac[x] * ifac[x - k] % mod;
    };
    LL ans = 0;
    for(int i = 1; i <= n; i++) {
        //A(n - i, i - 1) * fac(n - i);
        ans += A(n - i, i - 1) * fac[n - i] % mod;
        if(ans >= mod) ans -= mod;
    }
    cout << ans << endl;
}
int32_t main() {
#ifndef LOCAL
    ios::sync_with_stdio(0),cin.tie(0),cout.tie(0);
#endif
    int tt=1;
    //cin >> tt;
    while (tt--) 
    solve();
}

詳細信息

Test #1:

score: 100
Accepted
time: 0ms
memory: 3488kb

input:

1

output:

1

result:

ok 1 number(s): "1"

Test #2:

score: 0
Accepted
time: 0ms
memory: 3756kb

input:

2

output:

1

result:

ok 1 number(s): "1"

Test #3:

score: 0
Accepted
time: 0ms
memory: 3820kb

input:

10

output:

997920

result:

ok 1 number(s): "997920"

Test #4:

score: 0
Accepted
time: 0ms
memory: 3552kb

input:

100

output:

188898954

result:

ok 1 number(s): "188898954"

Test #5:

score: 0
Accepted
time: 0ms
memory: 3616kb

input:

4

output:

10

result:

ok 1 number(s): "10"

Test #6:

score: 0
Accepted
time: 0ms
memory: 3556kb

input:

8

output:

12336

result:

ok 1 number(s): "12336"

Test #7:

score: 0
Accepted
time: 0ms
memory: 3816kb

input:

16

output:

373118483

result:

ok 1 number(s): "373118483"

Test #8:

score: 0
Accepted
time: 0ms
memory: 3548kb

input:

32

output:

314585464

result:

ok 1 number(s): "314585464"

Test #9:

score: 0
Accepted
time: 0ms
memory: 3616kb

input:

64

output:

627827331

result:

ok 1 number(s): "627827331"

Test #10:

score: 0
Accepted
time: 0ms
memory: 3784kb

input:

128

output:

828497685

result:

ok 1 number(s): "828497685"

Test #11:

score: 0
Accepted
time: 0ms
memory: 3596kb

input:

256

output:

65697890

result:

ok 1 number(s): "65697890"

Test #12:

score: 0
Accepted
time: 0ms
memory: 3624kb

input:

512

output:

854187619

result:

ok 1 number(s): "854187619"

Test #13:

score: 0
Accepted
time: 0ms
memory: 3548kb

input:

1024

output:

513823539

result:

ok 1 number(s): "513823539"

Test #14:

score: 0
Accepted
time: 15ms
memory: 24340kb

input:

1361956

output:

617368199

result:

ok 1 number(s): "617368199"

Test #15:

score: 0
Accepted
time: 76ms
memory: 121516kb

input:

7579013

output:

827172636

result:

ok 1 number(s): "827172636"

Test #16:

score: 0
Accepted
time: 81ms
memory: 130464kb

input:

8145517

output:

710624331

result:

ok 1 number(s): "710624331"

Test #17:

score: 0
Accepted
time: 69ms
memory: 99004kb

input:

6140463

output:

707600568

result:

ok 1 number(s): "707600568"

Test #18:

score: 0
Accepted
time: 35ms
memory: 58164kb

input:

3515281

output:

698302413

result:

ok 1 number(s): "698302413"

Test #19:

score: 0
Accepted
time: 76ms
memory: 112028kb

input:

6969586

output:

69470392

result:

ok 1 number(s): "69470392"

Test #20:

score: 0
Accepted
time: 35ms
memory: 48128kb

input:

2888636

output:

433579983

result:

ok 1 number(s): "433579983"

Test #21:

score: 0
Accepted
time: 104ms
memory: 159336kb

input:

9999998

output:

758172780

result:

ok 1 number(s): "758172780"

Test #22:

score: 0
Accepted
time: 104ms
memory: 159296kb

input:

9999999

output:

605195495

result:

ok 1 number(s): "605195495"

Test #23:

score: 0
Accepted
time: 104ms
memory: 159244kb

input:

10000000

output:

866813682

result:

ok 1 number(s): "866813682"