結果

問題 No.2266 Fractions (hard)
ユーザー NyaanNyaanNyaanNyaan
提出日時 2023-04-10 19:31:31
言語 C++17
(gcc 12.3.0 + boost 1.83.0)
結果
AC  
実行時間 3,786 ms / 6,000 ms
コード長 33,730 bytes
コンパイル時間 3,625 ms
コンパイル使用メモリ 289,536 KB
実行使用メモリ 5,376 KB
最終ジャッジ日時 2024-04-15 23:05:12
合計ジャッジ時間 35,131 ms
ジャッジサーバーID
(参考情報)
judge5 / judge1
このコードへのチャレンジ
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テストケース

テストケース表示
入力 結果 実行時間
実行使用メモリ
testcase_00 AC 16 ms
5,248 KB
testcase_01 AC 1,784 ms
5,376 KB
testcase_02 AC 881 ms
5,376 KB
testcase_03 AC 2 ms
5,376 KB
testcase_04 AC 4 ms
5,376 KB
testcase_05 AC 9 ms
5,376 KB
testcase_06 AC 79 ms
5,376 KB
testcase_07 AC 31 ms
5,376 KB
testcase_08 AC 9 ms
5,376 KB
testcase_09 AC 4 ms
5,376 KB
testcase_10 AC 5 ms
5,376 KB
testcase_11 AC 2 ms
5,376 KB
testcase_12 AC 13 ms
5,376 KB
testcase_13 AC 1,268 ms
5,376 KB
testcase_14 AC 120 ms
5,376 KB
testcase_15 AC 148 ms
5,376 KB
testcase_16 AC 1,328 ms
5,376 KB
testcase_17 AC 1,054 ms
5,376 KB
testcase_18 AC 1,419 ms
5,376 KB
testcase_19 AC 2,140 ms
5,376 KB
testcase_20 AC 106 ms
5,376 KB
testcase_21 AC 1,674 ms
5,376 KB
testcase_22 AC 667 ms
5,376 KB
testcase_23 AC 185 ms
5,376 KB
testcase_24 AC 185 ms
5,376 KB
testcase_25 AC 1,885 ms
5,376 KB
testcase_26 AC 184 ms
5,376 KB
testcase_27 AC 1,566 ms
5,376 KB
testcase_28 AC 186 ms
5,376 KB
testcase_29 AC 184 ms
5,376 KB
testcase_30 AC 185 ms
5,376 KB
testcase_31 AC 185 ms
5,376 KB
testcase_32 AC 1,284 ms
5,376 KB
testcase_33 AC 2 ms
5,376 KB
testcase_34 AC 2,684 ms
5,376 KB
testcase_35 AC 2,558 ms
5,376 KB
testcase_36 AC 3,786 ms
5,376 KB
testcase_37 AC 2,075 ms
5,376 KB
権限があれば一括ダウンロードができます
コンパイルメッセージ
main.cpp:870:7: warning: 'template<class _Category, class _Tp, class _Distance, class _Pointer, class _Reference> struct std::iterator' is deprecated [-Wdeprecated-declarations]
  870 |     : iterator<bidirectional_iterator_tag, Data, ptrdiff_t, Data*, Data&> {
      |       ^~~~~~~~
In file included from /home/linuxbrew/.linuxbrew/Cellar/gcc/13.2.0/include/c++/13/bits/stl_algobase.h:65,
                 from /home/linuxbrew/.linuxbrew/Cellar/gcc/13.2.0/include/c++/13/algorithm:60,
                 from main.cpp:11:
/home/linuxbrew/.linuxbrew/Cellar/gcc/13.2.0/include/c++/13/bits/stl_iterator_base_types.h:127:34: note: declared here
  127 |     struct _GLIBCXX17_DEPRECATED iterator
      |                                  ^~~~~~~~
main.cpp:872:7: warning: 'template<class _Category, class _Tp, class _Distance, class _Pointer, class _Reference> struct std::iterator' is deprecated [-Wdeprecated-declarations]
  872 |       iterator<bidirectional_iterator_tag, Data, ptrdiff_t, Data*, Data&>;
      |       ^~~~~~~~
/home/linuxbrew/.linuxbrew/Cellar/gcc/13.2.0/include/c++/13/bits/stl_iterator_base_types.h:127:34: note: declared here
  127 |     struct _GLIBCXX17_DEPRECATED iterator
      |                                  ^~~~~~~~
In file included from /home/linuxbrew/.linuxbrew/Cellar/gcc/13.2.0/include/c++/13/functional:59,
                 from main.cpp:31:
In copy constructor 'std::function<_Res(_ArgTypes ...)>::function(const std::function<_Res(_ArgTypes ...)>&) [with _Res = int; _ArgTypes = {long long int}]',
    inlined from 'enumerate_mf_prefix_sum<T>::enumerate_mf_prefix_sum(const std::function<T(long long int)>&, const std::function<T(long long int)>&) [with T = int]' at main.cpp:1241:9,
    inlined from 'Nyaan::pl calc(Nyaan::ll, Nyaan::ll)' at main.cpp:1259:42:
/home/linuxbrew/.linuxbrew/Cellar/gcc/13.2.0/include/c++/13/bits/std_function.h:391:17: warning: '<anonymous>' may be used uninitialized [-Wmaybe-uninitialized]
  391 |             __x._M_manager(_M_func

ソースコード

diff #

/**
 *  date : 2023-04-10 19:31:23
 */

#define NDEBUG
using namespace std;

// intrinstic
#include <immintrin.h>

#include <algorithm>
#include <array>
#include <bitset>
#include <cassert>
#include <cctype>
#include <cfenv>
#include <cfloat>
#include <chrono>
#include <cinttypes>
#include <climits>
#include <cmath>
#include <complex>
#include <cstdarg>
#include <cstddef>
#include <cstdint>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <deque>
#include <fstream>
#include <functional>
#include <initializer_list>
#include <iomanip>
#include <ios>
#include <iostream>
#include <istream>
#include <iterator>
#include <limits>
#include <list>
#include <map>
#include <memory>
#include <new>
#include <numeric>
#include <ostream>
#include <queue>
#include <random>
#include <set>
#include <sstream>
#include <stack>
#include <streambuf>
#include <string>
#include <tuple>
#include <type_traits>
#include <typeinfo>
#include <unordered_map>
#include <unordered_set>
#include <utility>
#include <vector>

// utility
namespace Nyaan {
using ll = long long;
using i64 = long long;
using u64 = unsigned long long;
using i128 = __int128_t;
using u128 = __uint128_t;

template <typename T>
using V = vector<T>;
template <typename T>
using VV = vector<vector<T>>;
using vi = vector<int>;
using vl = vector<long long>;
using vd = V<double>;
using vs = V<string>;
using vvi = vector<vector<int>>;
using vvl = vector<vector<long long>>;

template <typename T, typename U>
struct P : pair<T, U> {
  template <typename... Args>
  P(Args... args) : pair<T, U>(args...) {}

  using pair<T, U>::first;
  using pair<T, U>::second;

  P &operator+=(const P &r) {
    first += r.first;
    second += r.second;
    return *this;
  }
  P &operator-=(const P &r) {
    first -= r.first;
    second -= r.second;
    return *this;
  }
  P &operator*=(const P &r) {
    first *= r.first;
    second *= r.second;
    return *this;
  }
  template <typename S>
  P &operator*=(const S &r) {
    first *= r, second *= r;
    return *this;
  }
  P operator+(const P &r) const { return P(*this) += r; }
  P operator-(const P &r) const { return P(*this) -= r; }
  P operator*(const P &r) const { return P(*this) *= r; }
  template <typename S>
  P operator*(const S &r) const {
    return P(*this) *= r;
  }
  P operator-() const { return P{-first, -second}; }
};

using pl = P<ll, ll>;
using pi = P<int, int>;
using vp = V<pl>;

constexpr int inf = 1001001001;
constexpr long long infLL = 4004004004004004004LL;

template <typename T>
int sz(const T &t) {
  return t.size();
}

template <typename T, typename U>
inline bool amin(T &x, U y) {
  return (y < x) ? (x = y, true) : false;
}
template <typename T, typename U>
inline bool amax(T &x, U y) {
  return (x < y) ? (x = y, true) : false;
}

template <typename T>
inline T Max(const vector<T> &v) {
  return *max_element(begin(v), end(v));
}
template <typename T>
inline T Min(const vector<T> &v) {
  return *min_element(begin(v), end(v));
}
template <typename T>
inline long long Sum(const vector<T> &v) {
  return accumulate(begin(v), end(v), 0LL);
}

template <typename T>
int lb(const vector<T> &v, const T &a) {
  return lower_bound(begin(v), end(v), a) - begin(v);
}
template <typename T>
int ub(const vector<T> &v, const T &a) {
  return upper_bound(begin(v), end(v), a) - begin(v);
}

constexpr long long TEN(int n) {
  long long ret = 1, x = 10;
  for (; n; x *= x, n >>= 1) ret *= (n & 1 ? x : 1);
  return ret;
}

template <typename T, typename U>
pair<T, U> mkp(const T &t, const U &u) {
  return make_pair(t, u);
}

template <typename T>
vector<T> mkrui(const vector<T> &v, bool rev = false) {
  vector<T> ret(v.size() + 1);
  if (rev) {
    for (int i = int(v.size()) - 1; i >= 0; i--) ret[i] = v[i] + ret[i + 1];
  } else {
    for (int i = 0; i < int(v.size()); i++) ret[i + 1] = ret[i] + v[i];
  }
  return ret;
};

template <typename T>
vector<T> mkuni(const vector<T> &v) {
  vector<T> ret(v);
  sort(ret.begin(), ret.end());
  ret.erase(unique(ret.begin(), ret.end()), ret.end());
  return ret;
}

template <typename F>
vector<int> mkord(int N,F f) {
  vector<int> ord(N);
  iota(begin(ord), end(ord), 0);
  sort(begin(ord), end(ord), f);
  return ord;
}

template <typename T>
vector<int> mkinv(vector<T> &v) {
  int max_val = *max_element(begin(v), end(v));
  vector<int> inv(max_val + 1, -1);
  for (int i = 0; i < (int)v.size(); i++) inv[v[i]] = i;
  return inv;
}

vector<int> mkiota(int n) {
  vector<int> ret(n);
  iota(begin(ret), end(ret), 0);
  return ret;
}

template <typename T>
T mkrev(const T &v) {
  T w{v};
  reverse(begin(w), end(w));
  return w;
}

template <typename T>
bool nxp(vector<T> &v) {
  return next_permutation(begin(v), end(v));
}

template <typename T>
using minpq = priority_queue<T, vector<T>, greater<T>>;

}  // namespace Nyaan

// bit operation
namespace Nyaan {
__attribute__((target("popcnt"))) inline int popcnt(const u64 &a) {
  return _mm_popcnt_u64(a);
}
inline int lsb(const u64 &a) { return a ? __builtin_ctzll(a) : 64; }
inline int ctz(const u64 &a) { return a ? __builtin_ctzll(a) : 64; }
inline int msb(const u64 &a) { return a ? 63 - __builtin_clzll(a) : -1; }
template <typename T>
inline int gbit(const T &a, int i) {
  return (a >> i) & 1;
}
template <typename T>
inline void sbit(T &a, int i, bool b) {
  if (gbit(a, i) != b) a ^= T(1) << i;
}
constexpr long long PW(int n) { return 1LL << n; }
constexpr long long MSK(int n) { return (1LL << n) - 1; }
}  // namespace Nyaan

// inout
namespace Nyaan {

template <typename T, typename U>
ostream &operator<<(ostream &os, const pair<T, U> &p) {
  os << p.first << " " << p.second;
  return os;
}
template <typename T, typename U>
istream &operator>>(istream &is, pair<T, U> &p) {
  is >> p.first >> p.second;
  return is;
}

template <typename T>
ostream &operator<<(ostream &os, const vector<T> &v) {
  int s = (int)v.size();
  for (int i = 0; i < s; i++) os << (i ? " " : "") << v[i];
  return os;
}
template <typename T>
istream &operator>>(istream &is, vector<T> &v) {
  for (auto &x : v) is >> x;
  return is;
}

istream &operator>>(istream &is, __int128_t &x) {
  string S;
  is >> S;
  x = 0;
  int flag = 0;
  for (auto &c : S) {
    if (c == '-') {
      flag = true;
      continue;
    }
    x *= 10;
    x += c - '0';
  }
  if (flag) x = -x;
  return is;
}

istream &operator>>(istream &is, __uint128_t &x) {
  string S;
  is >> S;
  x = 0;
  for (auto &c : S) {
    x *= 10;
    x += c - '0';
  }
  return is;
}

ostream &operator<<(ostream &os, __int128_t x) {
  if (x == 0) return os << 0;
  if (x < 0) os << '-', x = -x;
  string S;
  while (x) S.push_back('0' + x % 10), x /= 10;
  reverse(begin(S), end(S));
  return os << S;
}
ostream &operator<<(ostream &os, __uint128_t x) {
  if (x == 0) return os << 0;
  string S;
  while (x) S.push_back('0' + x % 10), x /= 10;
  reverse(begin(S), end(S));
  return os << S;
}

void in() {}
template <typename T, class... U>
void in(T &t, U &...u) {
  cin >> t;
  in(u...);
}

void out() { cout << "\n"; }
template <typename T, class... U, char sep = ' '>
void out(const T &t, const U &...u) {
  cout << t;
  if (sizeof...(u)) cout << sep;
  out(u...);
}

struct IoSetupNya {
  IoSetupNya() {
    cin.tie(nullptr);
    ios::sync_with_stdio(false);
    cout << fixed << setprecision(15);
    cerr << fixed << setprecision(7);
  }
} iosetupnya;

}  // namespace Nyaan

// debug

#ifdef NyaanDebug
#define trc(...) (void(0))
#else
#define trc(...) (void(0))
#endif

#ifdef NyaanLocal
#define trc2(...) (void(0))
#else
#define trc2(...) (void(0))
#endif

// macro
#define each(x, v) for (auto&& x : v)
#define each2(x, y, v) for (auto&& [x, y] : v)
#define all(v) (v).begin(), (v).end()
#define rep(i, N) for (long long i = 0; i < (long long)(N); i++)
#define repr(i, N) for (long long i = (long long)(N)-1; i >= 0; i--)
#define rep1(i, N) for (long long i = 1; i <= (long long)(N); i++)
#define repr1(i, N) for (long long i = (N); (long long)(i) > 0; i--)
#define reg(i, a, b) for (long long i = (a); i < (b); i++)
#define regr(i, a, b) for (long long i = (b)-1; i >= (a); i--)
#define fi first
#define se second
#define ini(...)   \
  int __VA_ARGS__; \
  in(__VA_ARGS__)
#define inl(...)         \
  long long __VA_ARGS__; \
  in(__VA_ARGS__)
#define ins(...)      \
  string __VA_ARGS__; \
  in(__VA_ARGS__)
#define in2(s, t)                           \
  for (int i = 0; i < (int)s.size(); i++) { \
    in(s[i], t[i]);                         \
  }
#define in3(s, t, u)                        \
  for (int i = 0; i < (int)s.size(); i++) { \
    in(s[i], t[i], u[i]);                   \
  }
#define in4(s, t, u, v)                     \
  for (int i = 0; i < (int)s.size(); i++) { \
    in(s[i], t[i], u[i], v[i]);             \
  }
#define die(...)             \
  do {                       \
    Nyaan::out(__VA_ARGS__); \
    return;                  \
  } while (0)

namespace Nyaan {
void solve();
}
int main() { Nyaan::solve(); }

//




#ifdef _MSC_VER
#include <intrin.h>
#endif

namespace atcoder {

namespace internal {

// @param m `1 <= m`
// @return x mod m
constexpr long long safe_mod(long long x, long long m) {
    x %= m;
    if (x < 0) x += m;
    return x;
}

// Fast modular multiplication by barrett reduction
// Reference: https://en.wikipedia.org/wiki/Barrett_reduction
// NOTE: reconsider after Ice Lake
struct barrett {
    unsigned int _m;
    unsigned long long im;

    // @param m `1 <= m < 2^31`
    barrett(unsigned int m) : _m(m), im((unsigned long long)(-1) / m + 1) {}

    // @return m
    unsigned int umod() const { return _m; }

    // @param a `0 <= a < m`
    // @param b `0 <= b < m`
    // @return `a * b % m`
    unsigned int mul(unsigned int a, unsigned int b) const {
        // [1] m = 1
        // a = b = im = 0, so okay

        // [2] m >= 2
        // im = ceil(2^64 / m)
        // -> im * m = 2^64 + r (0 <= r < m)
        // let z = a*b = c*m + d (0 <= c, d < m)
        // a*b * im = (c*m + d) * im = c*(im*m) + d*im = c*2^64 + c*r + d*im
        // c*r + d*im < m * m + m * im < m * m + 2^64 + m <= 2^64 + m * (m + 1) < 2^64 * 2
        // ((ab * im) >> 64) == c or c + 1
        unsigned long long z = a;
        z *= b;
#ifdef _MSC_VER
        unsigned long long x;
        _umul128(z, im, &x);
#else
        unsigned long long x =
            (unsigned long long)(((unsigned __int128)(z)*im) >> 64);
#endif
        unsigned int v = (unsigned int)(z - x * _m);
        if (_m <= v) v += _m;
        return v;
    }
};

// @param n `0 <= n`
// @param m `1 <= m`
// @return `(x ** n) % m`
constexpr long long pow_mod_constexpr(long long x, long long n, int m) {
    if (m == 1) return 0;
    unsigned int _m = (unsigned int)(m);
    unsigned long long r = 1;
    unsigned long long y = safe_mod(x, m);
    while (n) {
        if (n & 1) r = (r * y) % _m;
        y = (y * y) % _m;
        n >>= 1;
    }
    return r;
}

// Reference:
// M. Forisek and J. Jancina,
// Fast Primality Testing for Integers That Fit into a Machine Word
// @param n `0 <= n`
constexpr bool is_prime_constexpr(int n) {
    if (n <= 1) return false;
    if (n == 2 || n == 7 || n == 61) return true;
    if (n % 2 == 0) return false;
    long long d = n - 1;
    while (d % 2 == 0) d /= 2;
    constexpr long long bases[3] = {2, 7, 61};
    for (long long a : bases) {
        long long t = d;
        long long y = pow_mod_constexpr(a, t, n);
        while (t != n - 1 && y != 1 && y != n - 1) {
            y = y * y % n;
            t <<= 1;
        }
        if (y != n - 1 && t % 2 == 0) {
            return false;
        }
    }
    return true;
}
template <int n> constexpr bool is_prime = is_prime_constexpr(n);

// @param b `1 <= b`
// @return pair(g, x) s.t. g = gcd(a, b), xa = g (mod b), 0 <= x < b/g
constexpr std::pair<long long, long long> inv_gcd(long long a, long long b) {
    a = safe_mod(a, b);
    if (a == 0) return {b, 0};

    // Contracts:
    // [1] s - m0 * a = 0 (mod b)
    // [2] t - m1 * a = 0 (mod b)
    // [3] s * |m1| + t * |m0| <= b
    long long s = b, t = a;
    long long m0 = 0, m1 = 1;

    while (t) {
        long long u = s / t;
        s -= t * u;
        m0 -= m1 * u;  // |m1 * u| <= |m1| * s <= b

        // [3]:
        // (s - t * u) * |m1| + t * |m0 - m1 * u|
        // <= s * |m1| - t * u * |m1| + t * (|m0| + |m1| * u)
        // = s * |m1| + t * |m0| <= b

        auto tmp = s;
        s = t;
        t = tmp;
        tmp = m0;
        m0 = m1;
        m1 = tmp;
    }
    // by [3]: |m0| <= b/g
    // by g != b: |m0| < b/g
    if (m0 < 0) m0 += b / s;
    return {s, m0};
}

// Compile time primitive root
// @param m must be prime
// @return primitive root (and minimum in now)
constexpr int primitive_root_constexpr(int m) {
    if (m == 2) return 1;
    if (m == 167772161) return 3;
    if (m == 469762049) return 3;
    if (m == 754974721) return 11;
    if (m == 998244353) return 3;
    int divs[20] = {};
    divs[0] = 2;
    int cnt = 1;
    int x = (m - 1) / 2;
    while (x % 2 == 0) x /= 2;
    for (int i = 3; (long long)(i)*i <= x; i += 2) {
        if (x % i == 0) {
            divs[cnt++] = i;
            while (x % i == 0) {
                x /= i;
            }
        }
    }
    if (x > 1) {
        divs[cnt++] = x;
    }
    for (int g = 2;; g++) {
        bool ok = true;
        for (int i = 0; i < cnt; i++) {
            if (pow_mod_constexpr(g, (m - 1) / divs[i], m) == 1) {
                ok = false;
                break;
            }
        }
        if (ok) return g;
    }
}
template <int m> constexpr int primitive_root = primitive_root_constexpr(m);

}  // namespace internal

}  // namespace atcoder


namespace atcoder {

long long pow_mod(long long x, long long n, int m) {
    assert(0 <= n && 1 <= m);
    if (m == 1) return 0;
    internal::barrett bt((unsigned int)(m));
    unsigned int r = 1, y = (unsigned int)(internal::safe_mod(x, m));
    while (n) {
        if (n & 1) r = bt.mul(r, y);
        y = bt.mul(y, y);
        n >>= 1;
    }
    return r;
}

long long inv_mod(long long x, long long m) {
    assert(1 <= m);
    auto z = internal::inv_gcd(x, m);
    assert(z.first == 1);
    return z.second;
}

// (rem, mod)
std::pair<long long, long long> crt(const std::vector<long long>& r,
                                    const std::vector<long long>& m) {
    assert(r.size() == m.size());
    int n = int(r.size());
    // Contracts: 0 <= r0 < m0
    long long r0 = 0, m0 = 1;
    for (int i = 0; i < n; i++) {
        assert(1 <= m[i]);
        long long r1 = internal::safe_mod(r[i], m[i]), m1 = m[i];
        if (m0 < m1) {
            std::swap(r0, r1);
            std::swap(m0, m1);
        }
        if (m0 % m1 == 0) {
            if (r0 % m1 != r1) return {0, 0};
            continue;
        }
        // assume: m0 > m1, lcm(m0, m1) >= 2 * max(m0, m1)

        // (r0, m0), (r1, m1) -> (r2, m2 = lcm(m0, m1));
        // r2 % m0 = r0
        // r2 % m1 = r1
        // -> (r0 + x*m0) % m1 = r1
        // -> x*u0*g % (u1*g) = (r1 - r0) (u0*g = m0, u1*g = m1)
        // -> x = (r1 - r0) / g * inv(u0) (mod u1)

        // im = inv(u0) (mod u1) (0 <= im < u1)
        long long g, im;
        std::tie(g, im) = internal::inv_gcd(m0, m1);

        long long u1 = (m1 / g);
        // |r1 - r0| < (m0 + m1) <= lcm(m0, m1)
        if ((r1 - r0) % g) return {0, 0};

        // u1 * u1 <= m1 * m1 / g / g <= m0 * m1 / g = lcm(m0, m1)
        long long x = (r1 - r0) / g % u1 * im % u1;

        // |r0| + |m0 * x|
        // < m0 + m0 * (u1 - 1)
        // = m0 + m0 * m1 / g - m0
        // = lcm(m0, m1)
        r0 += x * m0;
        m0 *= u1;  // -> lcm(m0, m1)
        if (r0 < 0) r0 += m0;
    }
    return {r0, m0};
}

long long floor_sum(long long n, long long m, long long a, long long b) {
    long long ans = 0;
    if (a >= m) {
        ans += (n - 1) * n * (a / m) / 2;
        a %= m;
    }
    if (b >= m) {
        ans += n * (b / m);
        b %= m;
    }

    long long y_max = (a * n + b) / m, x_max = (y_max * m - b);
    if (y_max == 0) return ans;
    ans += (n - (x_max + a - 1) / a) * y_max;
    ans += floor_sum(y_max, a, m, (a - x_max % a) % a);
    return ans;
}

}  // namespace atcoder


//

using namespace std;


using namespace std;

namespace BinaryGCDImpl {
using u64 = unsigned long long;
using i8 = char;

inline u64 binary_gcd(u64 a, u64 b) {
  if (a == 0 || b == 0) return a + b;
  i8 n = __builtin_ctzll(a);
  i8 m = __builtin_ctzll(b);
  a >>= n;
  b >>= m;
  n = min(n, m);
  while (a != b) {
    u64 d = a - b;
    i8 s = __builtin_ctzll(d);
    bool f = a > b;
    b = f ? b : a;
    a = (f ? d : -d) >> s;
  }
  return a << n;
}
}  // namespace BinaryGCDImpl

long long fgcd(long long a, long long b) {
  return BinaryGCDImpl::binary_gcd(abs(a), abs(b));
}

/**
 * @brief binary GCD
 */

// T : 値, U : 比較用
template <typename T, typename U>
struct RationalBase {
  using R = RationalBase;
  using Key = T;
  T x, y;
  RationalBase() : x(0), y(1) {}
  RationalBase(T _x, T _y = 1) : x(_x), y(_y) {
    assert(y != 0);
    if (y == -1) x = -x, y = -y;
    if (y != 1) {
      T g;
      if constexpr (is_same_v<T, int> || is_same_v<T, long long>) {
        g = fgcd(abs(x), abs(y));
      } else {
        assert(false);
      }
      if (g != 0) x /= g, y /= g;
      if (y < 0) x = -x, y = -y;
    }
  }
  // y = 0 の代入も認める
  static R raw(T _x, T _y) {
    R r;
    r.x = _x, r.y = _y;
    return r;
  }
  friend R operator+(const R& l, const R& r) {
    if (l.y == r.y) return R{l.x + r.x, l.y};
    return R{l.x * r.y + l.y * r.x, l.y * r.y};
  }
  friend R operator-(const R& l, const R& r) {
    if (l.y == r.y) return R{l.x - r.x, l.y};
    return R{l.x * r.y - l.y * r.x, l.y * r.y};
  }
  friend R operator*(const R& l, const R& r) { return R{l.x * r.x, l.y * r.y}; }
  friend R operator/(const R& l, const R& r) { return R{l.x * r.y, l.y * r.x}; }
  R& operator+=(const R& r) { return (*this) = (*this) + r; }
  R& operator-=(const R& r) { return (*this) = (*this) - r; }
  R& operator*=(const R& r) { return (*this) = (*this) * r; }
  R& operator/=(const R& r) { return (*this) = (*this) / r; }
  R operator-() const { return raw(-x, y); }
  R inverse() const {
    assert(x != 0);
    R r = raw(y, x);
    if (r.y < 0) r.x = -r.x, r.y = -r.y;
    return r;
  }
  R pow(long long p) const {
    R res{1}, base{*this};
    while (p) {
      if (p & 1) res *= base;
      base *= base;
      p >>= 1;
    }
    return res;
  }
  friend bool operator==(const R& l, const R& r) {
    return l.x == r.x && l.y == r.y;
  };
  friend bool operator!=(const R& l, const R& r) {
    return l.x != r.x || l.y != r.y;
  };
  friend bool operator<(const R& l, const R& r) {
    return U{l.x} * r.y < U{l.y} * r.x;
  };
  friend bool operator<=(const R& l, const R& r) { return l < r || l == r; }
  friend bool operator>(const R& l, const R& r) {
    return U{l.x} * r.y > U{l.y} * r.x;
  };
  friend bool operator>=(const R& l, const R& r) { return l > r || l == r; }
  friend ostream& operator<<(ostream& os, const R& r) {
    os << r.x;
    if (r.x != 0 && r.y != 1) os << "/" << r.y;
    return os;
  }

  T toMint(T mod) {
    assert(mod != 0);
    T a = y, b = mod, u = 1, v = 0, t;
    while (b > 0) {
      t = a / b;
      swap(a -= t * b, b);
      swap(u -= t * v, v);
    }
    return U((u % mod + mod) % mod) * x % mod;
  }
};

using Rational = RationalBase<long long, __int128_t>;

template <typename R = Rational>
struct Binomial {
  vector<R> fc;
  Binomial(int = 0) { fc.emplace_back(1); }
  void extend() {
    int n = fc.size();
    R nxt = fc.back() * n;
    fc.push_back(nxt);
  }
  R fac(int n) {
    if (n < 0) return 0;
    while ((int)fc.size() <= n) extend();
    return fc[n];
  }
  R finv(int n) {
    if (n < 0) return 0;
    return fac(n).inverse();
  }
  R inv(int n) {
    if (n < 0) return -inv(-n);
    return R{1, max(n, 1)};
  }
  R C(int n, int r) {
    if (n < 0 or r < 0 or n < r) return R{0};
    return fac(n) * finv(n - r) * finv(r);
  }
  R operator()(int n, int r) { return C(n, r); }
  template <typename I>
  R multinomial(const vector<I>& r) {
    static_assert(is_integral<I>::value == true);
    int n = 0;
    for (auto& x : r) {
      if (x < 0) return R{0};
      n += x;
    }
    R res = fac(n);
    for (auto& x : r) res *= finv(x);
    return res;
  }

  template <typename I>
  R operator()(const vector<I>& r) {
    return multinomial(r);
  }
};

//

using namespace std;



using namespace std;

namespace HashMapImpl {
using u32 = uint32_t;
using u64 = uint64_t;

template <typename Key, typename Data>
struct HashMapBase;

template <typename Key, typename Data>
struct itrB
    : iterator<bidirectional_iterator_tag, Data, ptrdiff_t, Data*, Data&> {
  using base =
      iterator<bidirectional_iterator_tag, Data, ptrdiff_t, Data*, Data&>;
  using ptr = typename base::pointer;
  using ref = typename base::reference;

  u32 i;
  HashMapBase<Key, Data>* p;

  explicit constexpr itrB() : i(0), p(nullptr) {}
  explicit constexpr itrB(u32 _i, HashMapBase<Key, Data>* _p) : i(_i), p(_p) {}
  explicit constexpr itrB(u32 _i, const HashMapBase<Key, Data>* _p)
      : i(_i), p(const_cast<HashMapBase<Key, Data>*>(_p)) {}
  friend void swap(itrB& l, itrB& r) { swap(l.i, r.i), swap(l.p, r.p); }
  friend bool operator==(const itrB& l, const itrB& r) { return l.i == r.i; }
  friend bool operator!=(const itrB& l, const itrB& r) { return l.i != r.i; }
  const ref operator*() const {
    return const_cast<const HashMapBase<Key, Data>*>(p)->data[i];
  }
  ref operator*() { return p->data[i]; }
  ptr operator->() const { return &(p->data[i]); }

  itrB& operator++() {
    assert(i != p->cap && "itr::operator++()");
    do {
      i++;
      if (i == p->cap) break;
      if (p->occupied_flag[i] && !p->deleted_flag[i]) break;
    } while (true);
    return (*this);
  }
  itrB operator++(int) {
    itrB it(*this);
    ++(*this);
    return it;
  }
  itrB& operator--() {
    do {
      i--;
      if (p->occupied_flag[i] && !p->deleted_flag[i]) break;
      assert(i != 0 && "itr::operator--()");
    } while (true);
    return (*this);
  }
  itrB operator--(int) {
    itrB it(*this);
    --(*this);
    return it;
  }
};

template <typename Key, typename Data>
struct HashMapBase {
  using u32 = uint32_t;
  using u64 = uint64_t;
  using iterator = itrB<Key, Data>;
  using itr = iterator;

 protected:
  template <typename K>
  inline u64 randomized(const K& key) const {
    return u64(key) ^ r;
  }

  template <typename K,
            enable_if_t<is_same<K, Key>::value, nullptr_t> = nullptr,
            enable_if_t<is_integral<K>::value, nullptr_t> = nullptr>
  inline u32 inner_hash(const K& key) const {
    return (randomized(key) * 11995408973635179863ULL) >> shift;
  }
  template <
      typename K, enable_if_t<is_same<K, Key>::value, nullptr_t> = nullptr,
      enable_if_t<is_integral<decltype(K::first)>::value, nullptr_t> = nullptr,
      enable_if_t<is_integral<decltype(K::second)>::value, nullptr_t> = nullptr>
  inline u32 inner_hash(const K& key) const {
    u64 a = randomized(key.first), b = randomized(key.second);
    a *= 11995408973635179863ULL;
    b *= 10150724397891781847ULL;
    return (a + b) >> shift;
  }
  template <typename K,
            enable_if_t<is_same<K, Key>::value, nullptr_t> = nullptr,
            enable_if_t<is_integral<typename K::value_type>::value, nullptr_t> =
                nullptr>
  inline u32 inner_hash(const K& key) const {
    static constexpr u64 mod = (1LL << 61) - 1;
    static constexpr u64 base = 950699498548472943ULL;
    u64 res = 0;
    for (auto& elem : key) {
      __uint128_t x = __uint128_t(res) * base + (randomized(elem) & mod);
      res = (x & mod) + (x >> 61);
    }
    __uint128_t x = __uint128_t(res) * base;
    res = (x & mod) + (x >> 61);
    if (res >= mod) res -= mod;
    return res >> (shift - 3);
  }

  template <typename D = Data,
            enable_if_t<is_same<D, Key>::value, nullptr_t> = nullptr>
  inline u32 hash(const D& dat) const {
    return inner_hash(dat);
  }
  template <
      typename D = Data,
      enable_if_t<is_same<decltype(D::first), Key>::value, nullptr_t> = nullptr>
  inline u32 hash(const D& dat) const {
    return inner_hash(dat.first);
  }

  template <typename D = Data,
            enable_if_t<is_same<D, Key>::value, nullptr_t> = nullptr>
  inline Key data_to_key(const D& dat) const {
    return dat;
  }
  template <
      typename D = Data,
      enable_if_t<is_same<decltype(D::first), Key>::value, nullptr_t> = nullptr>
  inline Key data_to_key(const D& dat) const {
    return dat.first;
  }

  void reallocate(u32 ncap) {
    vector<Data> ndata(ncap);
    vector<bool> nf(ncap);
    shift = 64 - __lg(ncap);
    for (u32 i = 0; i < cap; i++) {
      if (occupied_flag[i] && !deleted_flag[i]) {
        u32 h = hash(data[i]);
        while (nf[h]) h = (h + 1) & (ncap - 1);
        ndata[h] = move(data[i]);
        nf[h] = true;
      }
    }
    data.swap(ndata);
    occupied_flag.swap(nf);
    cap = ncap;
    occupied = s;
    deleted_flag.resize(cap);
    fill(std::begin(deleted_flag), std::end(deleted_flag), false);
  }

  inline bool extend_rate(u32 x) const { return x * 2 >= cap; }

  inline bool shrink_rate(u32 x) const {
    return HASHMAP_DEFAULT_SIZE < cap && x * 10 <= cap;
  }

  inline void extend() { reallocate(cap << 1); }

  inline void shrink() { reallocate(cap >> 1); }

 public:
  u32 cap, s, occupied;
  vector<Data> data;
  vector<bool> occupied_flag, deleted_flag;
  u32 shift;
  static u64 r;
  static constexpr uint32_t HASHMAP_DEFAULT_SIZE = 4;

  explicit HashMapBase()
      : cap(HASHMAP_DEFAULT_SIZE),
        s(0),
        occupied(0),
        data(cap),
        occupied_flag(cap),
        deleted_flag(cap),
        shift(64 - __lg(cap)) {}

  itr begin() const {
    u32 h = 0;
    while (h != cap) {
      if (occupied_flag[h] && !deleted_flag[h]) break;
      h++;
    }
    return itr(h, this);
  }
  itr end() const { return itr(this->cap, this); }

  friend itr begin(const HashMapBase& h) { return h.begin(); }
  friend itr end(const HashMapBase& h) { return h.end(); }

  itr find(const Key& key) const {
    u32 h = inner_hash(key);
    while (true) {
      if (occupied_flag[h] == false) return this->end();
      if (data_to_key(data[h]) == key) {
        if (deleted_flag[h] == true) return this->end();
        return itr(h, this);
      }
      h = (h + 1) & (cap - 1);
    }
  }

  bool contain(const Key& key) const { return find(key) != this->end(); }

  itr insert(const Data& d) {
    u32 h = hash(d);
    while (true) {
      if (occupied_flag[h] == false) {
        if (extend_rate(occupied + 1)) {
          extend();
          h = hash(d);
          continue;
        }
        data[h] = d;
        occupied_flag[h] = true;
        ++occupied, ++s;
        return itr(h, this);
      }
      if (data_to_key(data[h]) == data_to_key(d)) {
        if (deleted_flag[h] == true) {
          data[h] = d;
          deleted_flag[h] = false;
          ++s;
        }
        return itr(h, this);
      }
      h = (h + 1) & (cap - 1);
    }
  }

  // tips for speed up :
  // if return value is unnecessary, make argument_2 false.
  itr erase(itr it, bool get_next = true) {
    if (it == this->end()) return this->end();
    s--;
    if (!get_next) {
      this->deleted_flag[it.i] = true;
      if (shrink_rate(s)) shrink();
      return this->end();
    }
    itr nxt = it;
    nxt++;
    this->deleted_flag[it.i] = true;
    if (shrink_rate(s)) {
      Data d = data[nxt.i];
      shrink();
      it = find(data_to_key(d));
    }
    return nxt;
  }

  itr erase(const Key& key) { return erase(find(key)); }

  int count(const Key& key) { return find(key) == end() ? 0 : 1; }

  bool empty() const { return s == 0; }

  int size() const { return s; }

  void clear() {
    fill(std::begin(occupied_flag), std::end(occupied_flag), false);
    fill(std::begin(deleted_flag), std::end(deleted_flag), false);
    s = occupied = 0;
  }

  void reserve(int n) {
    if (n <= 0) return;
    n = 1 << min(23, __lg(n) + 2);
    if (cap < u32(n)) reallocate(n);
  }
};

template <typename Key, typename Data>
uint64_t HashMapBase<Key, Data>::r =
    chrono::duration_cast<chrono::nanoseconds>(
        chrono::high_resolution_clock::now().time_since_epoch())
        .count();

}  // namespace HashMapImpl

/**
 * @brief Hash Map(base) (ハッシュマップ・基底クラス)
 */

template <typename Key, typename Val>
struct HashMap : HashMapImpl::HashMapBase<Key, pair<Key, Val>> {
  using base = typename HashMapImpl::HashMapBase<Key, pair<Key, Val>>;
  using HashMapImpl::HashMapBase<Key, pair<Key, Val>>::HashMapBase;
  using Data = pair<Key, Val>;

  Val& operator[](const Key& k) {
    typename base::u32 h = base::inner_hash(k);
    while (true) {
      if (base::occupied_flag[h] == false) {
        if (base::extend_rate(base::occupied + 1)) {
          base::extend();
          h = base::hash(k);
          continue;
        }
        base::data[h].first = k;
        base::data[h].second = Val();
        base::occupied_flag[h] = true;
        ++base::occupied, ++base::s;
        return base::data[h].second;
      }
      if (base::data[h].first == k) {
        if (base::deleted_flag[h] == true) {
          base::data[h].second = Val();
          base::deleted_flag[h] = false;
          ++base::s;
        }
        return base::data[h].second;
      }
      h = (h + 1) & (base::cap - 1);
    }
  }

  typename base::itr emplace(const Key& key, const Val& val) {
    return base::insert(Data(key, val));
  }
};

/*
 * @brief ハッシュマップ(連想配列)
 * @docs docs/hashmap/hashmap.md
 **/

namespace EnumerateQuotientImpl {
long long fast_div(long long a, long long b) { return 1.0 * a / b; };
long long slow_div(long long a, long long b) { return a / b; };
}  // namespace EnumerateQuotientImpl

// { (q, l, r) : forall x in (l,r], floor(N/x) = q }
// を引数に取る関数f(q, l, r)を渡す。範囲が左に半開なのに注意
template <typename T, typename F>
void enumerate_quotient(T N, const F& f) {
  T sq = sqrt(N);
  while ((sq + 1) * (sq + 1) <= N) sq++;
  while (sq * sq > N) sq--;

#define FUNC(d)                       \
  T upper = N, quo = 0;               \
  while (upper > sq) {                \
    T thres = d(N, (++quo + 1));      \
    f(quo, thres, upper);             \
    upper = thres;                    \
  }                                   \
  while (upper > 0) {                 \
    f(d(N, upper), upper - 1, upper); \
    upper--;                          \
  }

  if (N <= 1e12) {
    FUNC(EnumerateQuotientImpl::fast_div);
  } else {
    FUNC(EnumerateQuotientImpl::slow_div);
  }
#undef FUNC
}

/**
 *  @brief 商の列挙
 */
/**
 * S(f, n) = f(1) + f(2) + ... + f(n) とする
 * f と g のディリクレ積を h とする
 * S(h, n) と S(g, n) が高速に計算できる, かつ g(1) = 1 のとき
 * S(f, N/i) を O(N^{3/4}) で列挙できる
 *
 * うまくやると O~(N^{2/3}) に落ちたり g(1) != 1 に対応できる
 * https://codeforces.com/blog/entry/54150
 */
template <typename T>
struct enumerate_mf_prefix_sum {
  unordered_map<long long, T> dp;
  function<T(long long)> sg;
  function<T(long long)> sh;
  enumerate_mf_prefix_sum(const function<T(long long)>& _sg,
                          const function<T(long long)>& _sh)
      : sg(_sg), sh(_sh) {}
  T get(long long n) {
    if (dp.count(n)) return dp[n];
    T res = sh(n);
    enumerate_quotient(n, [&](long long q, long long l, long long r) {
      if (q != n) res -= get(q) * (sg(r) - sg(l));
    });
    return dp[n] = res;
  }
  T operator()(long long n) { return get(n); }
};

using namespace Nyaan;

// k 番目に小さい
pl calc(ll N, ll K) {
  auto sg = [](int n) -> int { return n; };
  auto sh = [](int) -> int { return 1; };
  enumerate_mf_prefix_sum<int> moe(sg, sh);

  auto cnt = [&](Rational f) -> ll {
    // trc2(f);
    ll s = 0;
    enumerate_quotient(N, [&](ll q, ll l, ll r) {
      ll x = 0;
      x += atcoder::floor_sum(r + 1, f.y, f.x, 0);
      x -= atcoder::floor_sum(l + 1, f.y, f.x, 0);
      s += x * moe(q);
    });
    /*
    each(i, mop) {
      if (i > N) break;
      s += i * ll(f.x) / int(f.y);
    }
    */
    // trc2(f, s);
    return s;
  };
  Rational L{0, 1};
  Rational M{1, 2};
  Rational R{1, 1};
  while (true) {
    // trc2(L.x, L.y, M.x, M.y, R.x, R.y);
    ll c = cnt(M);
    if (c == K) {
      break;
    }
    if (c < K) {
      L = M;
      for (ll i = 2;; i *= 2) {
        Rational f{L.x + R.x * i, L.y + R.y * i};
        if (max(f.x, f.y) > N) break;
        if (cnt(f) == K) return {f.x, f.y};
        if (cnt(f) < K) {
          L = f;
        } else {
          break;
        }
      }
    } else {
      R = M;
      for (ll i = 2;; i *= 2) {
        Rational f{L.x * i + R.x, L.y * i + R.y};
        if (max(f.x, f.y) > N) break;
        if (cnt(f) == K) return {f.x, f.y};
        if (cnt(f) >= K) {
          R = f;
        } else {
          break;
        }
      }
    }
    M = Rational{L.x + R.x, L.y + R.y};
  }
  return {M.x, M.y};
}

void q() {
  inl(N, K);
  auto g = [](ll n) -> ll { return n; };
  auto h = [](ll n) -> ll { return n * (n + 1) / 2; };
  enumerate_mf_prefix_sum<ll> tot(g, h);

  ll s = tot(N) - 1;
  trc(s);
  ll p = -1, q = -1;
  if (K <= s) {
    tie(p, q) = calc(N, K);
  } else if (K == s + 1) {
    p = q = 1;
  } else if (K <= s * 2 + 1) {
    tie(q, p) = calc(N, 2 * s + 1 - (K - 1));
  } else {
    // do nothing
  }
  if (p == -1) {
    out(-1);
  } else {
    cout << p << "/" << q << "\n";
  }
}

void Nyaan::solve() {
  int t = 1;
  // in(t);
  while (t--) q();
}
0