Submission #54963919

Source Code Expand

#include <bits/stdc++.h>
#include "atcoder/modint"

using namespace std;
using Fp = atcoder::modint998244353;
using i64 = long long;

int main() {
    i64 n;
    int k;
    cin >> n >> k;

    const Fp p = Fp(2 * (n - 1)) / Fp(n).pow(2);
    const Fp q = Fp(2) / Fp(n).pow(2);
    Fp d = 1;
    for (int i = 0; i < k; ++i) {
        d = (1 - q - p) * d + q;
    }

    const Fp u = Fp(n + 2) / 2;
    cout << (d + u * (1 - d)).val() << endl;
}

Submission Info

Submission Time
Task E - Random Swaps of Balls
User Cyanmond
Language C++ 20 (gcc 12.2)
Score 1
Code Size 466 Byte
Status AC
Exec Time 2 ms
Memory 3688 KiB

Judge Result

Set Name Sample All
Score / Max Score 0 / 0 1 / 1
Status
AC × 3
AC × 36
Set Name Test Cases
Sample 00_sample_00.txt, 00_sample_01.txt, 00_sample_02.txt
All 00_sample_00.txt, 00_sample_01.txt, 00_sample_02.txt, 01_internal_00.txt, 01_internal_01.txt, 01_internal_02.txt, 01_internal_03.txt, 01_internal_04.txt, 01_internal_05.txt, 01_internal_06.txt, 01_internal_07.txt, 01_internal_08.txt, 01_internal_09.txt, 01_internal_10.txt, 01_internal_11.txt, 01_internal_12.txt, 01_internal_13.txt, 01_internal_14.txt, 01_internal_15.txt, 01_internal_16.txt, 01_internal_17.txt, 01_internal_18.txt, 01_internal_19.txt, 01_internal_20.txt, 01_internal_21.txt, 01_internal_22.txt, 01_internal_23.txt, 01_internal_24.txt, 01_internal_25.txt, 01_internal_26.txt, 01_internal_27.txt, 01_internal_28.txt, 01_internal_29.txt, 01_internal_30.txt, 01_internal_31.txt, 01_internal_32.txt
Case Name Status Exec Time Memory
00_sample_00.txt AC 1 ms 3484 KiB
00_sample_01.txt AC 1 ms 3552 KiB
00_sample_02.txt AC 1 ms 3512 KiB
01_internal_00.txt AC 1 ms 3688 KiB
01_internal_01.txt AC 2 ms 3556 KiB
01_internal_02.txt AC 1 ms 3512 KiB
01_internal_03.txt AC 1 ms 3504 KiB
01_internal_04.txt AC 1 ms 3492 KiB
01_internal_05.txt AC 1 ms 3488 KiB
01_internal_06.txt AC 1 ms 3620 KiB
01_internal_07.txt AC 1 ms 3512 KiB
01_internal_08.txt AC 1 ms 3548 KiB
01_internal_09.txt AC 1 ms 3488 KiB
01_internal_10.txt AC 2 ms 3616 KiB
01_internal_11.txt AC 1 ms 3552 KiB
01_internal_12.txt AC 2 ms 3552 KiB
01_internal_13.txt AC 1 ms 3504 KiB
01_internal_14.txt AC 1 ms 3440 KiB
01_internal_15.txt AC 2 ms 3552 KiB
01_internal_16.txt AC 1 ms 3552 KiB
01_internal_17.txt AC 1 ms 3488 KiB
01_internal_18.txt AC 1 ms 3488 KiB
01_internal_19.txt AC 1 ms 3440 KiB
01_internal_20.txt AC 2 ms 3552 KiB
01_internal_21.txt AC 1 ms 3552 KiB
01_internal_22.txt AC 1 ms 3680 KiB
01_internal_23.txt AC 2 ms 3552 KiB
01_internal_24.txt AC 1 ms 3504 KiB
01_internal_25.txt AC 1 ms 3500 KiB
01_internal_26.txt AC 1 ms 3472 KiB
01_internal_27.txt AC 1 ms 3492 KiB
01_internal_28.txt AC 1 ms 3508 KiB
01_internal_29.txt AC 2 ms 3500 KiB
01_internal_30.txt AC 2 ms 3552 KiB
01_internal_31.txt AC 1 ms 3616 KiB
01_internal_32.txt AC 2 ms 3556 KiB