結果
| 問題 |
No.1728 [Cherry 3rd Tune] Bullet
|
| コンテスト | |
| ユーザー |
 tokusakurai
|
| 提出日時 | 2021-10-29 23:12:50 |
| 言語 | C++17 (gcc 13.3.0 + boost 1.87.0) |
| 結果 |
AC
|
| 実行時間 | 69 ms / 2,000 ms |
| コード長 | 6,910 bytes |
| コンパイル時間 | 2,941 ms |
| コンパイル使用メモリ | 207,200 KB |
| 最終ジャッジ日時 | 2025-01-25 09:35:42 |
|
ジャッジサーバーID （参考情報） |
judge2 / judge2 |
（要ログイン）
| ファイルパターン | 結果 |
|---|---|
| other | AC * 27 |
ソースコード
#include <bits/stdc++.h>
using namespace std;
#define rep(i, n) for (int i = 0; i < n; i++)
#define rep2(i, x, n) for (int i = x; i <= n; i++)
#define rep3(i, x, n) for (int i = x; i >= n; i--)
#define each(e, v) for (auto &e : v)
#define pb push_back
#define eb emplace_back
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define sz(x) (int)x.size()
using ll = long long;
using pii = pair<int, int>;
using pil = pair<int, ll>;
using pli = pair<ll, int>;
using pll = pair<ll, ll>;
template <typename T>
bool chmax(T &x, const T &y) {
return (x < y) ? (x = y, true) : false;
}
template <typename T>
bool chmin(T &x, const T &y) {
return (x > y) ? (x = y, true) : false;
}
template <typename T>
int flg(T x, int i) {
return (x >> i) & 1;
}
template <typename T>
void print(const vector<T> &v, T x = 0) {
int n = v.size();
for (int i = 0; i < n; i++) cout << v[i] + x << (i == n - 1 ? '\n' : ' ');
}
template <typename T>
void printn(const vector<T> &v, T x = 0) {
int n = v.size();
for (int i = 0; i < n; i++) cout << v[i] + x << '\n';
}
template <typename T>
int lb(const vector<T> &v, T x) {
return lower_bound(begin(v), end(v), x) - begin(v);
}
template <typename T>
int ub(const vector<T> &v, T x) {
return upper_bound(begin(v), end(v), x) - begin(v);
}
template <typename T>
void rearrange(vector<T> &v) {
sort(begin(v), end(v));
v.erase(unique(begin(v), end(v)), end(v));
}
template <typename T>
vector<int> id_sort(const vector<T> &v, bool greater = false) {
int n = v.size();
vector<int> ret(n);
iota(begin(ret), end(ret), 0);
sort(begin(ret), end(ret), [&](int i, int j) { return greater ? v[i] > v[j] : v[i] < v[j]; });
return ret;
}
struct io_setup {
io_setup() {
ios_base::sync_with_stdio(false);
cin.tie(NULL);
cout << fixed << setprecision(15);
}
} io_setup;
const int inf = (1 << 30) - 1;
const ll INF = (1LL << 60) - 1;
const int MOD = 1000000007;
// const int MOD = 998244353;
template <typename T>
vector<T> divisors(const T &n) {
vector<T> ret;
for (T i = 1; i * i <= n; i++) {
if (n % i == 0) {
ret.push_back(i);
if (i * i != n) ret.push_back(n / i);
}
}
sort(begin(ret), end(ret));
return ret;
}
template <typename T>
vector<pair<T, int>> prime_factor(T n) {
vector<pair<T, int>> ret;
for (T i = 2; i * i <= n; i++) {
int cnt = 0;
while (n % i == 0) cnt++, n /= i;
if (cnt > 0) ret.emplace_back(i, cnt);
}
if (n > 1) ret.emplace_back(n, 1);
return ret;
}
template <typename T>
bool is_prime(const T &n) {
if (n == 1) return false;
for (T i = 2; i * i <= n; i++) {
if (n % i == 0) return false;
}
return true;
}
// 1,2,...,nのうちkと互いに素である自然数の個数
template <typename T>
T coprime(T n, T k) {
vector<pair<T, int>> ps = prime_factor(k);
int m = ps.size();
T ret = 0;
for (int i = 0; i < (1 << m); i++) {
T prd = 1;
for (int j = 0; j < m; j++) {
if ((i >> j) & 1) prd *= ps[j].first;
}
ret += (__builtin_parity(i) ? -1 : 1) * (n / prd);
}
return ret;
}
vector<bool> Eratosthenes(const int &n) {
vector<bool> ret(n + 1, true);
if (n >= 0) ret[0] = false;
if (n >= 1) ret[1] = false;
for (int i = 2; i * i <= n; i++) {
if (!ret[i]) continue;
for (int j = i + i; j <= n; j += i) ret[j] = false;
}
return ret;
}
vector<int> Eratosthenes2(const int &n) {
vector<int> ret(n + 1);
iota(begin(ret), end(ret), 0);
if (n >= 0) ret[0] = -1;
if (n >= 1) ret[1] = -1;
for (int i = 2; i * i <= n; i++) {
if (ret[i] < i) continue;
for (int j = i + i; j <= n; j += i) ret[j] = min(ret[j], i);
}
return ret;
}
template <int mod>
struct Mod_Int {
int x;
Mod_Int() : x(0) {}
Mod_Int(long long y) : x(y >= 0 ? y % mod : (mod - (-y) % mod) % mod) {}
static int get_mod() { return mod; }
Mod_Int &operator+=(const Mod_Int &p) {
if ((x += p.x) >= mod) x -= mod;
return *this;
}
Mod_Int &operator-=(const Mod_Int &p) {
if ((x += mod - p.x) >= mod) x -= mod;
return *this;
}
Mod_Int &operator*=(const Mod_Int &p) {
x = (int)(1LL * x * p.x % mod);
return *this;
}
Mod_Int &operator/=(const Mod_Int &p) {
*this *= p.inverse();
return *this;
}
Mod_Int &operator++() { return *this += Mod_Int(1); }
Mod_Int operator++(int) {
Mod_Int tmp = *this;
++*this;
return tmp;
}
Mod_Int &operator--() { return *this -= Mod_Int(1); }
Mod_Int operator--(int) {
Mod_Int tmp = *this;
--*this;
return tmp;
}
Mod_Int operator-() const { return Mod_Int(-x); }
Mod_Int operator+(const Mod_Int &p) const { return Mod_Int(*this) += p; }
Mod_Int operator-(const Mod_Int &p) const { return Mod_Int(*this) -= p; }
Mod_Int operator*(const Mod_Int &p) const { return Mod_Int(*this) *= p; }
Mod_Int operator/(const Mod_Int &p) const { return Mod_Int(*this) /= p; }
bool operator==(const Mod_Int &p) const { return x == p.x; }
bool operator!=(const Mod_Int &p) const { return x != p.x; }
Mod_Int inverse() const {
assert(*this != Mod_Int(0));
return pow(mod - 2);
}
Mod_Int pow(long long k) const {
Mod_Int now = *this, ret = 1;
for (; k > 0; k >>= 1, now *= now) {
if (k & 1) ret *= now;
}
return ret;
}
friend ostream &operator<<(ostream &os, const Mod_Int &p) { return os << p.x; }
friend istream &operator>>(istream &is, Mod_Int &p) {
long long a;
is >> a;
p = Mod_Int<mod>(a);
return is;
}
};
using mint = Mod_Int<MOD>;
int main() {
int T;
cin >> T;
while (T--) {
int N, C;
cin >> N >> C;
vector<int> ds = divisors(N);
vector<pii> ps = prime_factor(N);
int K = sz(ds);
vector<int> c(K, 1);
rep(i, K) {
int memo = ds[i];
each(e, ps) {
int t = 0;
while (memo % e.first == 0) {
memo /= e.first;
t++;
}
if (t >= 2) c[i] = 0;
if (t == 1) c[i] *= -1;
}
}
vector<int> cnt(K, 0);
rep(i, K) {
rep(j, i + 1) {
if (ds[i] % ds[j] == 0) cnt[i] += c[j] * (ds[i] / ds[j]);
}
}
// rep(i, K) cout << ds[i] << ' ' << cnt[i] << '\n';
mint ans = 0;
rep(i, K) {
int x = N / ds[i];
ans += mint(C).pow(2 * x) * cnt[i];
}
ans += mint(C).pow(N) * N;
cout << ans / mint(2 * N) << '\n';
}
}