QOJ.ac

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
#348118#8339. Rooted Treeucup-team1191#AC ✓1176ms3736kbC++202.6kb2024-03-09 17:01:532024-03-09 17:01:54

Judging History

你现在查看的是最新测评结果

  • [2024-03-09 17:01:54]
  • 评测
  • 测评结果:AC
  • 用时:1176ms
  • 内存:3736kb
  • [2024-03-09 17:01:53]
  • 提交

answer

#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef long double ld;
#define TIME (clock() * 1.0 / CLOCKS_PER_SEC)

const int MOD = 1'000'000'009;

using ull = unsigned long long;
template <int MD>
struct ModInt {
    using M = ModInt;
//    static int MD;
    int v;
    ModInt(ll _v = 0) { set_v(int(_v % MD + MD)); }
    inline M& set_v(int _v) {
        v = (_v < MD) ? _v : _v - MD;
        return *this;
    }
    inline explicit operator bool() const { return v != 0; }
    inline M operator-() const { return M() - *this; }
    inline M operator+(const M& r) const { return M().set_v(v + r.v); }
    inline M operator-(const M& r) const { return M().set_v(v + MD - r.v); }
    inline M operator*(const M& r) const { return M().set_v(int((ull)v * r.v % MD)); }
    inline M operator/(const M& r) const { return *this * r.inv(); }
    inline M& operator+=(const M& r) { return *this = *this + r; }
    inline M& operator-=(const M& r) { return *this = *this - r; }
    inline M& operator*=(const M& r) { return *this = *this * r; }
    inline M& operator/=(const M& r) { return *this = *this / r; }
    inline bool operator==(const M& r) const { return v == r.v; }
    inline bool operator!=(const M& r) const { return v != r.v; }
    inline M inv() const;
    inline friend istream& operator>>(istream& is, M& r) { ll x; is >> x; r = M(x); return is; }
    inline friend ostream& operator<<(ostream& os, const M& r) { return os << r.v; }
};

template<int MD>
ModInt<MD> pow(ModInt<MD> x, ll n) {
//ModInt pow(ModInt x, ll n) {
    ModInt<MD> r = 1;
    //ModInt r = 1;
    while (n) {
        if (n & 1) r *= x;
        x *= x;
        n >>= 1;
    }
    return r;
}

template<int MD>
ModInt<MD> ModInt<MD>::inv() const { return pow(*this, MD - 2); }
//ModInt ModInt::inv() const { return pow(*this, MD - 2); }

// if MD is from input
// this line is necessary, read later as you wish
//int ModInt::MD;

using Mint = ModInt<MOD>;
//using Mint = ModInt;

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

    Mint exp_sum = 0;
    Mint exp_ans = 0;
    for (int i = 0; i < k; i++) {
        int cnt = i * (m - 1) + 1;
        Mint avg_deg = exp_sum * Mint(cnt).inv();
        exp_sum += avg_deg * (m - 1) + m;
        exp_ans += (avg_deg + 1) * m;
    }

    cout << exp_ans << "\n";
}

int main() {
#ifdef ONPC
    freopen("input", "r", stdin);
#endif
    ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);

    int t = 1;
    //cin >> t;
    while (t--) {
        solve();
    }

    return 0;
}

詳細信息

Test #1:

score: 100
Accepted
time: 0ms
memory: 3608kb

input:

6 2

output:

18

result:

ok 1 number(s): "18"

Test #2:

score: 0
Accepted
time: 0ms
memory: 3684kb

input:

2 6

output:

600000038

result:

ok 1 number(s): "600000038"

Test #3:

score: 0
Accepted
time: 73ms
memory: 3668kb

input:

83 613210

output:

424200026

result:

ok 1 number(s): "424200026"

Test #4:

score: 0
Accepted
time: 790ms
memory: 3736kb

input:

48 6713156

output:

198541581

result:

ok 1 number(s): "198541581"

Test #5:

score: 0
Accepted
time: 0ms
memory: 3608kb

input:

1 111

output:

6216

result:

ok 1 number(s): "6216"

Test #6:

score: 0
Accepted
time: 856ms
memory: 3604kb

input:

28 7304152

output:

457266679

result:

ok 1 number(s): "457266679"

Test #7:

score: 0
Accepted
time: 483ms
memory: 3664kb

input:

38 4101162

output:

232117382

result:

ok 1 number(s): "232117382"

Test #8:

score: 0
Accepted
time: 1167ms
memory: 3688kb

input:

51 9921154

output:

340670552

result:

ok 1 number(s): "340670552"

Test #9:

score: 0
Accepted
time: 212ms
memory: 3612kb

input:

79 1801157

output:

620550406

result:

ok 1 number(s): "620550406"

Test #10:

score: 0
Accepted
time: 637ms
memory: 3696kb

input:

22 5417157

output:

457449071

result:

ok 1 number(s): "457449071"

Test #11:

score: 0
Accepted
time: 378ms
memory: 3672kb

input:

25 3210162

output:

36368303

result:

ok 1 number(s): "36368303"

Test #12:

score: 0
Accepted
time: 344ms
memory: 3608kb

input:

67 2919160

output:

935195555

result:

ok 1 number(s): "935195555"

Test #13:

score: 0
Accepted
time: 1013ms
memory: 3676kb

input:

77 8613163

output:

482832472

result:

ok 1 number(s): "482832472"

Test #14:

score: 0
Accepted
time: 1176ms
memory: 3736kb

input:

90 10000000

output:

275581651

result:

ok 1 number(s): "275581651"

Test #15:

score: 0
Accepted
time: 1174ms
memory: 3664kb

input:

99 9999999

output:

126087169

result:

ok 1 number(s): "126087169"

Test #16:

score: 0
Accepted
time: 1176ms
memory: 3736kb

input:

100 10000000

output:

451590067

result:

ok 1 number(s): "451590067"

Extra Test:

score: 0
Extra Test Passed