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QOJ

IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#548350#8339. Rooted TreeHTensor#AC ✓208ms315752kbC++171.8kb2024-09-05 17:22:362024-09-05 17:22:36

Judging History

This is the latest submission verdict.

  • [2024-09-05 17:22:36]
  • Judged
  • Verdict: AC
  • Time: 208ms
  • Memory: 315752kb
  • [2024-09-05 17:22:36]
  • Submitted

answer

#include <bits/stdc++.h>
#define dd(x) cout << #x << "\n"
#define d(x) cout << #x  << ": " << x << "\n"
using namespace std;
#define int long long
using pii = pair<int, int>;
using vpii = vector<pii>;
using vi = vector<int>;
using vii = vector<vector<int>>;
using a3 = array<int, 3>;
const int inf = 0x3f3f3f3f3f3f3f3fLL;

const int mod = 1e9 + 9;
int qpow(int a, int b) {
    int res = 1;
    for (; b; b /= 2, a = a * a % mod) {
        if (b & 1) {
            res = res * a % mod;
        }
    }
    return res;
}
int inv(int a) {
    return qpow(a, mod - 2);
}
// 1-n的逆元
vector<int> linear_inv(int n) {
    vector<int> iv(n + 1);
    iv[1] = 1;
    for (int i = 2; i <= n; i++) {
        iv[i] = (mod - mod / i) * iv[mod % i] % mod;
    } 
    return iv;
}
// 任意n个数的逆元
vector<int> linear_inv(const vector<int> &a) {
    int n = a.size() - 1;
    vector<int> iv(n + 1), s(n + 1), sv(n + 1);
    s[0] = 1;
    for (int i = 1; i <= n; i++) {
        s[i] = s[i - 1] * a[i] % mod;
    }
    sv[n] = inv(s[n]);
    for (int i = n; i >= 1; i--) {
        sv[i - 1] = sv[i] * a[i] % mod;
    }
    for (int i = 1; i <= n; i++) {
        iv[i] = sv[i] * s[i - 1] % mod;
    }
    return iv;
}

int positive(int x) {
    return (x % mod + mod) % mod;
}

void solve() {
    int m, k; cin >> m >> k;
    vector<int> down(k + 1);
    for(int i = 1; i <= k; i++) {
        down[i] = i * m - i + 1;
    }
    down = linear_inv(down);
    vector<int> v(k + 1), dp(k + 1);
    
    for(int i = 1; i <= k; i++) {
        v[i] = positive(v[i - 1] + m * down[i]);
        dp[i] = positive(dp[i - 1] + m * (v[i - 1] + 1));
    }

    cout << dp[k] << "\n";
}

signed main() {
    ios::sync_with_stdio(false); cin.tie(0);
    int T = 1;
    while(T--) solve();
    return 0;
}

Details

Tip: Click on the bar to expand more detailed information

Test #1:

score: 100
Accepted
time: 0ms
memory: 3560kb

input:

6 2

output:

18

result:

ok 1 number(s): "18"

Test #2:

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

input:

2 6

output:

600000038

result:

ok 1 number(s): "600000038"

Test #3:

score: 0
Accepted
time: 12ms
memory: 22288kb

input:

83 613210

output:

424200026

result:

ok 1 number(s): "424200026"

Test #4:

score: 0
Accepted
time: 141ms
memory: 212940kb

input:

48 6713156

output:

198541581

result:

ok 1 number(s): "198541581"

Test #5:

score: 0
Accepted
time: 0ms
memory: 3632kb

input:

1 111

output:

6216

result:

ok 1 number(s): "6216"

Test #6:

score: 0
Accepted
time: 157ms
memory: 231264kb

input:

28 7304152

output:

457266679

result:

ok 1 number(s): "457266679"

Test #7:

score: 0
Accepted
time: 81ms
memory: 131424kb

input:

38 4101162

output:

232117382

result:

ok 1 number(s): "232117382"

Test #8:

score: 0
Accepted
time: 193ms
memory: 313096kb

input:

51 9921154

output:

340670552

result:

ok 1 number(s): "340670552"

Test #9:

score: 0
Accepted
time: 41ms
memory: 59652kb

input:

79 1801157

output:

620550406

result:

ok 1 number(s): "620550406"

Test #10:

score: 0
Accepted
time: 108ms
memory: 172476kb

input:

22 5417157

output:

457449071

result:

ok 1 number(s): "457449071"

Test #11:

score: 0
Accepted
time: 64ms
memory: 103504kb

input:

25 3210162

output:

36368303

result:

ok 1 number(s): "36368303"

Test #12:

score: 0
Accepted
time: 55ms
memory: 94392kb

input:

67 2919160

output:

935195555

result:

ok 1 number(s): "935195555"

Test #13:

score: 0
Accepted
time: 174ms
memory: 272292kb

input:

77 8613163

output:

482832472

result:

ok 1 number(s): "482832472"

Test #14:

score: 0
Accepted
time: 192ms
memory: 315752kb

input:

90 10000000

output:

275581651

result:

ok 1 number(s): "275581651"

Test #15:

score: 0
Accepted
time: 188ms
memory: 315576kb

input:

99 9999999

output:

126087169

result:

ok 1 number(s): "126087169"

Test #16:

score: 0
Accepted
time: 208ms
memory: 315684kb

input:

100 10000000

output:

451590067

result:

ok 1 number(s): "451590067"

Extra Test:

score: 0
Extra Test Passed