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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
#658977#8339. Rooted Treethe_foo#AC ✓1259ms159392kbC++202.5kb2024-10-19 18:05:402024-10-19 18:05:46

Judging History

你现在查看的是最新测评结果

  • [2024-10-19 18:05:46]
  • 评测
  • 测评结果:AC
  • 用时:1259ms
  • 内存:159392kb
  • [2024-10-19 18:05:40]
  • 提交

answer

#include <bits/stdc++.h>
using namespace std;

using LL = long long;
constexpr int mod = 1E9 + 9;

struct mint {
    LL x;
    mint(int _x = 0) {
        x = _x;
    }

    mint operator+(mint p) {
        LL res = x + p.x;
        while (res >= mod) res -= mod;
        return res;
    }

    mint operator-(mint p) {
        LL res = x - p.x;
        while (res < 0) res += mod;
        return res;
    }

    mint operator*(mint p) {
        return x * p.x % mod;
    }

    mint pow(LL b) {
        mint res = 1, a = *this;
        while (b) {
            if (b & 1) res = res * a;
            a = a * a;
            b >>= 1;
        }
        return res;
    }

    mint operator/(mint p) {
        return (*this) * p.pow(mod - 2);
    }
};

// void solve() {
//     int m, k;
//     cin >> m >> k;
//
//     vector<mint> pre(k + 1);
//     pre[0] = 1;
//     for (int i = 1; i <= k; i++) {
//         mint sum = mint(i) * (m - 1) + 1;
//         pre[i] = pre[i - 1] * (sum - 1) / sum;
//     }
//
//     vector<mint> suf(k + 1);
//     suf[k] = 1;
//     for (int i = k - 1; i >= 1; i--) {
//         mint sum = mint(i) * (m - 1) + 1;
//         suf[i] = suf[i + 1] * (sum - 1) / sum;
//     }
//
//     vector<mint> p(k + 1);
//     mint pp = 1;
//     p[0] = p[1] = 0;
//     for (int i = 2; i <= k; i++) {
//         p[i] = p[i - 1];
//         p[i] = (mint(1) - p[i - 1]) * suf[i - 1] + p[i];
//     }
//
//     for (int i = 1; i <= k; i++) {
//         cout << p[i].x << " \n"[i == k];
//     }
//
//     mint sum = 1, ans = 0;
//     for (int i = 1; i <= k; i++) {
//         sum = sum * m;
//         ans = ans + sum * i * (mint(1) - p[i]);
//     }
//
//     cout << ans.x << "\n";
// }

void solve() {
    int m, k;
    cin >> m >> k;

    vector<mint> dep(k + 1);
    dep[0] = 0;
    mint ans = 0;

    vector<mint> sum(k + 1);
    sum[0] = 1;
    for (int i = 1; i <= k; i++) {
        sum[i] = sum[i - 1] + m - 1;
    }

    for (int i = 1; i <= k; i++) {
        //mint t = dep[i - 1] / sum[i - 1];
        dep[i] = //(t + 1) * m - dep[i - 1];
            (dep[i-1]*sum[i-1]+(dep[i-1]+1)*m-dep[i-1])/sum[i];
        ans = ans + (dep[i-1]+1)*m;
    }
    cout << ans.x << "\n";
}

int main() {
    ios::sync_with_stdio(0);
    cin.tie(0);

    int t = 1;
    // cin >> t;
    while (t--) {
        solve();
    }
}
/*
 *2 3
333333337
500000005 666666673 750000007
0 750000007 375000004
17
*/

详细

Test #1:

score: 100
Accepted
time: 0ms
memory: 3800kb

input:

6 2

output:

18

result:

ok 1 number(s): "18"

Test #2:

score: 0
Accepted
time: 0ms
memory: 3748kb

input:

2 6

output:

600000038

result:

ok 1 number(s): "600000038"

Test #3:

score: 0
Accepted
time: 75ms
memory: 12628kb

input:

83 613210

output:

424200026

result:

ok 1 number(s): "424200026"

Test #4:

score: 0
Accepted
time: 841ms
memory: 107952kb

input:

48 6713156

output:

198541581

result:

ok 1 number(s): "198541581"

Test #5:

score: 0
Accepted
time: 0ms
memory: 3796kb

input:

1 111

output:

6216

result:

ok 1 number(s): "6216"

Test #6:

score: 0
Accepted
time: 921ms
memory: 117328kb

input:

28 7304152

output:

457266679

result:

ok 1 number(s): "457266679"

Test #7:

score: 0
Accepted
time: 511ms
memory: 67092kb

input:

38 4101162

output:

232117382

result:

ok 1 number(s): "232117382"

Test #8:

score: 0
Accepted
time: 1245ms
memory: 158444kb

input:

51 9921154

output:

340670552

result:

ok 1 number(s): "340670552"

Test #9:

score: 0
Accepted
time: 224ms
memory: 31352kb

input:

79 1801157

output:

620550406

result:

ok 1 number(s): "620550406"

Test #10:

score: 0
Accepted
time: 683ms
memory: 87824kb

input:

22 5417157

output:

457449071

result:

ok 1 number(s): "457449071"

Test #11:

score: 0
Accepted
time: 401ms
memory: 53292kb

input:

25 3210162

output:

36368303

result:

ok 1 number(s): "36368303"

Test #12:

score: 0
Accepted
time: 363ms
memory: 48752kb

input:

67 2919160

output:

935195555

result:

ok 1 number(s): "935195555"

Test #13:

score: 0
Accepted
time: 1084ms
memory: 137632kb

input:

77 8613163

output:

482832472

result:

ok 1 number(s): "482832472"

Test #14:

score: 0
Accepted
time: 1254ms
memory: 159300kb

input:

90 10000000

output:

275581651

result:

ok 1 number(s): "275581651"

Test #15:

score: 0
Accepted
time: 1259ms
memory: 159392kb

input:

99 9999999

output:

126087169

result:

ok 1 number(s): "126087169"

Test #16:

score: 0
Accepted
time: 1255ms
memory: 159384kb

input:

100 10000000

output:

451590067

result:

ok 1 number(s): "451590067"

Extra Test:

score: 0
Extra Test Passed