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:heavy_check_mark: verify/math/LC_stern_brocot_tree.test.cpp

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#define PROBLEM "https://judge.yosupo.jp/problem/stern_brocot_tree"

#include "template/template.hpp"
#include "math/stern-brocot-tree.hpp"
using sbt = SternBrocotTreeNode<ll>;

int main() {
  int t;
  in(t);
  while (t--) {
    string s;
    in(s);
    if (s == "ENCODE_PATH") {
      ll a, b;
      in(a, b);
      sbt x(a, b);
      cout << x.seq.size();
      for (auto v : x.seq) cout << " " << "LR"[v > 0] << " " << abs(v);
      cout << "\n";
    } else if (s == "DECODE_PATH") {
      sbt x;
      int k;
      in(k);
      rep(i, 0, k) {
        char dir;
        ll n;
        in(dir, n);
        if (dir == 'L')
          x.go_left(n);
        else
          x.go_right(n);
      }
      out(x.a, x.b);
    } else if (s == "LCA") {
      ll a, b, c, d;
      in(a, b, c, d);
      sbt x = sbt::lca(sbt(a, b), sbt(c, d));
      out(x.a, x.b);
    } else if (s == "ANCESTOR") {
      ll k, a, b;
      in(k, a, b);
      sbt x(a, b);
      ll d = x.depth() - k;
      if (d >= 0 && x.go_parent(d))
        out(x.a, x.b);
      else
        out(-1);
    } else if (s == "RANGE") {
      ll a, b;
      in(a, b);
      sbt x(a, b);
      out(x.lower_bound(), x.upper_bound());
    }
  }
}
#line 1 "verify/math/LC_stern_brocot_tree.test.cpp"
#define PROBLEM "https://judge.yosupo.jp/problem/stern_brocot_tree"

#line 2 "template/template.hpp"
#include <bits/stdc++.h>
using namespace std;

#line 2 "template/macro.hpp"
#define rep(i, a, b) for (int i = (a); i < (int)(b); i++)
#define rrep(i, a, b) for (int i = (int)(b) - 1; i >= (a); i--)
#define ALL(v) (v).begin(), (v).end()
#define UNIQUE(v) sort(ALL(v)), (v).erase(unique(ALL(v)), (v).end())
#define SZ(v) (int)v.size()
#define MIN(v) *min_element(ALL(v))
#define MAX(v) *max_element(ALL(v))
#define LB(v, x) int(lower_bound(ALL(v), (x)) - (v).begin())
#define UB(v, x) int(upper_bound(ALL(v), (x)) - (v).begin())
#define YN(b) cout << ((b) ? "YES" : "NO") << "\n";
#define Yn(b) cout << ((b) ? "Yes" : "No") << "\n";
#define yn(b) cout << ((b) ? "yes" : "no") << "\n";
#line 6 "template/template.hpp"

#line 2 "template/util.hpp"
using uint = unsigned int;
using ll = long long int;
using ull = unsigned long long;
using i128 = __int128_t;
using u128 = __uint128_t;

template <class T, class S = T>
S SUM(const vector<T> &a) {
  return accumulate(ALL(a), S(0));
}
template <class T>
inline bool chmin(T &a, T b) {
  if (a > b) {
    a = b;
    return true;
  }
  return false;
}
template <class T>
inline bool chmax(T &a, T b) {
  if (a < b) {
    a = b;
    return true;
  }
  return false;
}

template <class T>
int popcnt(T x) {
  return __builtin_popcountll(x);
}
template <class T>
int topbit(T x) {
  return (x == 0 ? -1 : 63 - __builtin_clzll(x));
}
template <class T>
int lowbit(T x) {
  return (x == 0 ? -1 : __builtin_ctzll(x));
}
#line 8 "template/template.hpp"

#line 2 "template/inout.hpp"
struct Fast {
  Fast() {
    cin.tie(nullptr);
    ios_base::sync_with_stdio(false);
    cout << fixed << setprecision(15);
  }
} fast;

template <class T1, class T2>
istream &operator>>(istream &is, pair<T1, T2> &p) {
  return is >> p.first >> p.second;
}
template <class T1, class T2>
ostream &operator<<(ostream &os, const pair<T1, T2> &p) {
  return os << p.first << " " << p.second;
}
template <class T>
istream &operator>>(istream &is, vector<T> &a) {
  for (auto &v : a) is >> v;
  return is;
}
template <class T>
ostream &operator<<(ostream &os, const vector<T> &a) {
  for (auto it = a.begin(); it != a.end();) {
    os << *it;
    if (++it != a.end()) os << " ";
  }
  return os;
}
template <class T>
ostream &operator<<(ostream &os, const set<T> &st) {
  os << "{";
  for (auto it = st.begin(); it != st.end();) {
    os << *it;
    if (++it != st.end()) os << ",";
  }
  os << "}";
  return os;
}
template <class T1, class T2>
ostream &operator<<(ostream &os, const map<T1, T2> &mp) {
  os << "{";
  for (auto it = mp.begin(); it != mp.end();) {
    os << it->first << ":" << it->second;
    if (++it != mp.end()) os << ",";
  }
  os << "}";
  return os;
}

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...);
}
#line 10 "template/template.hpp"

#line 2 "template/debug.hpp"
#ifdef LOCAL
#define debug 1
#define show(...) _show(0, #__VA_ARGS__, __VA_ARGS__)
#else
#define debug 0
#define show(...) true
#endif
template <class T>
void _show(int i, T name) {
  cerr << '\n';
}
template <class T1, class T2, class... T3>
void _show(int i, const T1 &a, const T2 &b, const T3 &...c) {
  for (; a[i] != ',' && a[i] != '\0'; i++) cerr << a[i];
  cerr << ":" << b << " ";
  _show(i + 1, a, c...);
}
#line 2 "math/stern-brocot-tree.hpp"

template <class T>
struct SternBrocotTreeNode {
  using Node = SternBrocotTreeNode;
  T la, lb, a, b, ra, rb;
  vector<T> seq;
  SternBrocotTreeNode() : la(0), lb(1), a(1), b(1), ra(1), rb(0) {}
  SternBrocotTreeNode(T x, T y) : SternBrocotTreeNode() {
    assert(x > 0 && y > 0);
    T g = gcd(x, y);
    x /= g, y /= g;
    bool is_right = true;
    while (x > 0 && y > 0) {
      T d = x / y;
      x -= d * y;
      if (is_right)
        go_right(d - (x == 0 ? 1 : 0));
      else
        go_left(d - (x == 0 ? 1 : 0));
      swap(x, y);
      is_right = !is_right;
    }
  }
  SternBrocotTreeNode(pair<T, T> p) : SternBrocotTreeNode(p.first, p.second) {}
  SternBrocotTreeNode(const vector<T> seq_) {
    for (auto& v : seq_) {
      assert(v != 0);
      if (v > 0)
        go_right(v);
      else
        go_left(v);
    }
    assert(seq == seq_);
  }
  pair<T, T> get() const { return {a, b}; }
  pair<T, T> lower_bound() const { return {la, lb}; }
  pair<T, T> upper_bound() const { return {ra, rb}; }

  void go_left(const T d = 1) {
    if (d <= 0) return;
    if (seq.empty() || seq.back() > 0) seq.push_back(0);
    seq.back() -= d;
    ra += la * d, rb += lb * d;
    a = la + ra, b = lb + rb;
  }
  void go_right(const T d = 1) {
    if (d <= 0) return;
    if (seq.empty() || seq.back() < 0) seq.push_back(0);
    seq.back() += d;
    la += ra * d, lb += rb * d;
    a = la + ra, b = lb + rb;
  }
  T depth() const {
    T d = 0;
    for (auto& v : seq) d += abs(v);
    return d;
  }
  static Node lca(const Node& x, const Node& y) {
    Node res;
    for (int i = 0; i < min(x.seq.size(), y.seq.size()); i++) {
      T d1 = x.seq[i], d2 = y.seq[i];
      if ((d1 > 0) != (d2 > 0)) break;
      if (d1 > 0)
        res.go_right(min(d1, d2));
      else
        res.go_left(min(-d1, -d2));
      if (d1 != d2) break;
    }
    return res;
  }
  bool go_parent(T d = 1) {
    if (d <= 0) return true;
    while (d > 0) {
      if (seq.empty()) return false;
      T d1 = min(d, abs(seq.back()));
      if (seq.back() > 0) {
        la -= ra * d1, lb -= rb * d1;
        seq.back() -= d1;
      } else {
        ra -= la * d1, rb -= lb * d1;
        seq.back() += d1;
      }
      a = la + ra, b = lb + rb;
      if (seq.back() <= 0) seq.pop_back();
      d -= d1;
    }
    return true;
  }
  template <class F>
  static Node binary_search(T n, F f) {
    Node res;
    while (true) {
      if (!f(res.a, res.b)) {
        T ok = 0, ng = min(res.la > 0 ? (n - res.ra) / res.la : n, res.lb > 0 ? (n - res.rb) / res.lb : n) + 1;
        while (ng - ok > 1) {
          T mid = (ok + ng) / 2;
          (!f(mid * res.la + res.ra, mid * res.lb + res.rb) ? ok : ng) = mid;
        }
        if (ok == 0) return res;
        res.go_left(ok);
      } else {
        T ok = 0, ng = min(res.ra > 0 ? (n - res.la) / res.ra : n, res.rb > 0 ? (n - res.lb) / res.rb : n) + 1;
        while (ng - ok > 1) {
          T mid = (ok + ng) / 2;
          (f(res.la + mid * res.ra, res.lb + mid * res.rb) ? ok : ng) = mid;
        }
        if (ok == 0) return res;
        res.go_left(ok);
      }
    }
  }
};

/**
 * @brief Stern-Brocot Tree
 * @docs docs/math/stern-brocot-tree.md
 */
#line 5 "verify/math/LC_stern_brocot_tree.test.cpp"
using sbt = SternBrocotTreeNode<ll>;

int main() {
  int t;
  in(t);
  while (t--) {
    string s;
    in(s);
    if (s == "ENCODE_PATH") {
      ll a, b;
      in(a, b);
      sbt x(a, b);
      cout << x.seq.size();
      for (auto v : x.seq) cout << " " << "LR"[v > 0] << " " << abs(v);
      cout << "\n";
    } else if (s == "DECODE_PATH") {
      sbt x;
      int k;
      in(k);
      rep(i, 0, k) {
        char dir;
        ll n;
        in(dir, n);
        if (dir == 'L')
          x.go_left(n);
        else
          x.go_right(n);
      }
      out(x.a, x.b);
    } else if (s == "LCA") {
      ll a, b, c, d;
      in(a, b, c, d);
      sbt x = sbt::lca(sbt(a, b), sbt(c, d));
      out(x.a, x.b);
    } else if (s == "ANCESTOR") {
      ll k, a, b;
      in(k, a, b);
      sbt x(a, b);
      ll d = x.depth() - k;
      if (d >= 0 && x.go_parent(d))
        out(x.a, x.b);
      else
        out(-1);
    } else if (s == "RANGE") {
      ll a, b;
      in(a, b);
      sbt x(a, b);
      out(x.lower_bound(), x.upper_bound());
    }
  }
}
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