#line 1 "main.cpp"
#define PROBLEM "https://yukicoder.me/problems/no/686"
#line 1 "library/my_template.hpp"
#pragma GCC optimize("Ofast")
#pragma GCC optimize("unroll-loops")

#include <bits/stdc++.h>

using namespace std;

using ll = long long;
using pi = pair<ll, ll>;
using vi = vector<ll>;
using u32 = unsigned int;
using u64 = unsigned long long;
using i128 = __int128;

template <class T>
using vc = vector<T>;
template <class T>
using vvc = vector<vc<T>>;
template <class T>
using vvvc = vector<vvc<T>>;
template <class T>
using vvvvc = vector<vvvc<T>>;
template <class T>
using vvvvvc = vector<vvvvc<T>>;
template <class T>
using pq = priority_queue<T>;
template <class T>
using pqg = priority_queue<T, vector<T>, greater<T>>;

#define vec(type, name, ...) vector<type> name(__VA_ARGS__)
#define vv(type, name, h, ...) \
  vector<vector<type>> name(h, vector<type>(__VA_ARGS__))
#define vvv(type, name, h, w, ...)   \
  vector<vector<vector<type>>> name( \
      h, vector<vector<type>>(w, vector<type>(__VA_ARGS__)))
#define vvvv(type, name, a, b, c, ...)       \
  vector<vector<vector<vector<type>>>> name( \
      a, vector<vector<vector<type>>>(       \
             b, vector<vector<type>>(c, vector<type>(__VA_ARGS__))))

// https://trap.jp/post/1224/
#define FOR1(a) for (ll _ = 0; _ < ll(a); ++_)
#define FOR2(i, a) for (ll i = 0; i < ll(a); ++i)
#define FOR3(i, a, b) for (ll i = a; i < ll(b); ++i)
#define FOR4(i, a, b, c) for (ll i = a; i < ll(b); i += (c))
#define FOR1_R(a) for (ll i = (a)-1; i >= ll(0); --i)
#define FOR2_R(i, a) for (ll i = (a)-1; i >= ll(0); --i)
#define FOR3_R(i, a, b) for (ll i = (b)-1; i >= ll(a); --i)
#define FOR4_R(i, a, b, c) for (ll i = (b)-1; i >= ll(a); i -= (c))
#define overload4(a, b, c, d, e, ...) e
#define FOR(...) overload4(__VA_ARGS__, FOR4, FOR3, FOR2, FOR1)(__VA_ARGS__)
#define FOR_R(...) \
  overload4(__VA_ARGS__, FOR4_R, FOR3_R, FOR2_R, FOR1_R)(__VA_ARGS__)

#define FOR_subset(t, s) for (ll t = s; t >= 0; t = (t == 0 ? -1 : (t - 1) & s))
#define all(x) x.begin(), x.end()
#define len(x) ll(x.size())
#define elif else if

#define eb emplace_back
#define mp make_pair
#define mt make_tuple
#define fi first
#define se second

#define stoi stoll

template <typename T, typename U>
T SUM(const vector<U> &A) {
  T sum = 0;
  for (auto &&a: A) sum += a;
  return sum;
}

#define MIN(v) *min_element(all(v))
#define MAX(v) *max_element(all(v))
#define LB(c, x) distance((c).begin(), lower_bound(all(c), (x)))
#define UB(c, x) distance((c).begin(), upper_bound(all(c), (x)))
#define UNIQUE(x) sort(all(x)), x.erase(unique(all(x)), x.end())

int popcnt(int x) { return __builtin_popcount(x); }
int popcnt(u32 x) { return __builtin_popcount(x); }
int popcnt(ll x) { return __builtin_popcountll(x); }
int popcnt(u64 x) { return __builtin_popcountll(x); }
// (0, 1, 2, 3, 4) -> (-1, 0, 1, 1, 2)
int topbit(int x) { return (x == 0 ? -1 : 31 - __builtin_clz(x)); }
int topbit(u32 x) { return (x == 0 ? -1 : 31 - __builtin_clz(x)); }
int topbit(ll x) { return (x == 0 ? -1 : 63 - __builtin_clzll(x)); }
int topbit(u64 x) { return (x == 0 ? -1 : 63 - __builtin_clzll(x)); }
// (0, 1, 2, 3, 4) -> (-1, 0, 1, 0, 2)
int lowbit(int x) { return (x == 0 ? -1 : __builtin_ctz(x)); }
int lowbit(u32 x) { return (x == 0 ? -1 : __builtin_ctz(x)); }
int lowbit(ll x) { return (x == 0 ? -1 : __builtin_ctzll(x)); }
int lowbit(u64 x) { return (x == 0 ? -1 : __builtin_ctzll(x)); }

template <typename T>
T pick(deque<T> &que) {
  T a = que.front();
  que.pop_front();
  return a;
}

template <typename T>
T pick(pq<T> &que) {
  T a = que.top();
  que.pop();
  return a;
}

template <typename T>
T pick(pqg<T> &que) {
  assert(que.size());
  T a = que.top();
  que.pop();
  return a;
}

template <typename T>
T pick(vc<T> &que) {
  assert(que.size());
  T a = que.back();
  que.pop_back();
  return a;
}

template <typename T, typename U>
T ceil(T x, U y) {
  return (x > 0 ? (x + y - 1) / y : x / y);
}

template <typename T, typename U>
T floor(T x, U y) {
  return (x > 0 ? x / y : (x - y + 1) / y);
}

template <typename T, typename U>
pair<T, T> divmod(T x, U y) {
  T q = floor(x, y);
  return {q, x - q * y};
}

template <typename F>
ll binary_search(F check, ll ok, ll ng) {
  assert(check(ok));
  while (abs(ok - ng) > 1) {
    auto x = (ng + ok) / 2;
    tie(ok, ng) = (check(x) ? mp(x, ng) : mp(ok, x));
  }
  return ok;
}

template <typename F>
double binary_search_real(F check, double ok, double ng, int iter = 100) {
  FOR(iter) {
    double x = (ok + ng) / 2;
    tie(ok, ng) = (check(x) ? mp(x, ng) : mp(ok, x));
  }
  return (ok + ng) / 2;
}

template <class T, class S>
inline bool chmax(T &a, const S &b) {
  return (a < b ? a = b, 1 : 0);
}
template <class T, class S>
inline bool chmin(T &a, const S &b) {
  return (a > b ? a = b, 1 : 0);
}

vc<int> s_to_vi(const string &S, char first_char) {
  vc<int> A(S.size());
  FOR(i, S.size()) { A[i] = S[i] - first_char; }
  return A;
}

template <typename T, typename U>
vector<T> cumsum(vector<U> &A, int off = 1) {
  int N = A.size();
  vector<T> B(N + 1);
  FOR(i, N) { B[i + 1] = B[i] + A[i]; }
  if (off == 0) B.erase(B.begin());
  return B;
}

template <typename CNT, typename T>
vc<CNT> bincount(const vc<T> &A, int size) {
  vc<CNT> C(size);
  for (auto &&x: A) { ++C[x]; }
  return C;
}

// stable
template <typename T>
vector<int> argsort(const vector<T> &A) {
  vector<int> ids(A.size());
  iota(all(ids), 0);
  sort(all(ids),
       [&](int i, int j) { return A[i] < A[j] || (A[i] == A[j] && i < j); });
  return ids;
}

// A[I[0]], A[I[1]], ...
template <typename T>
vc<T> rearrange(const vc<T> &A, const vc<int> &I) {
  int n = len(I);
  vc<T> B(n);
  FOR(i, n) B[i] = A[I[i]];
  return B;
}
#line 1 "library/other/io.hpp"
// based on yosupo's fastio
#include <unistd.h>

namespace detail {
template <typename T, decltype(&T::is_modint) = &T::is_modint>
std::true_type check_value(int);
template <typename T>
std::false_type check_value(long);
} // namespace detail

template <typename T>
struct is_modint : decltype(detail::check_value<T>(0)) {};
template <typename T>
using is_modint_t = enable_if_t<is_modint<T>::value>;
template <typename T>
using is_not_modint_t = enable_if_t<!is_modint<T>::value>;

struct Scanner {
  FILE *fp;
  char line[(1 << 15) + 1];
  size_t st = 0, ed = 0;
  void reread() {
    memmove(line, line + st, ed - st);
    ed -= st;
    st = 0;
    ed += fread(line + ed, 1, (1 << 15) - ed, fp);
    line[ed] = '\0';
  }
  bool succ() {
    while (true) {
      if (st == ed) {
        reread();
        if (st == ed) return false;
      }
      while (st != ed && isspace(line[st])) st++;
      if (st != ed) break;
    }
    if (ed - st <= 50) {
      bool sep = false;
      for (size_t i = st; i < ed; i++) {
        if (isspace(line[i])) {
          sep = true;
          break;
        }
      }
      if (!sep) reread();
    }
    return true;
  }
  template <class T, enable_if_t<is_same<T, string>::value, int> = 0>
  bool read_single(T &ref) {
    if (!succ()) return false;
    while (true) {
      size_t sz = 0;
      while (st + sz < ed && !isspace(line[st + sz])) sz++;
      ref.append(line + st, sz);
      st += sz;
      if (!sz || st != ed) break;
      reread();
    }
    return true;
  }
  template <class T, enable_if_t<is_integral<T>::value, int> = 0>
  bool read_single(T &ref) {
    if (!succ()) return false;
    bool neg = false;
    if (line[st] == '-') {
      neg = true;
      st++;
    }
    ref = T(0);
    while (isdigit(line[st])) { ref = 10 * ref + (line[st++] & 0xf); }
    if (neg) ref = -ref;
    return true;
  }
  template <class T, is_modint_t<T> * = nullptr>
  bool read_single(T &ref) {
    long long val = 0;
    bool f = read_single(val);
    ref = T(val);
    return f;
  }
  bool read_single(double &ref) {
    string s;
    if (!read_single(s)) return false;
    ref = std::stod(s);
    return true;
  }
  bool read_single(char &ref) {
    string s;
    if (!read_single(s) || s.size() != 1) return false;
    ref = s[0];
    return true;
  }
  template <class T>
  bool read_single(vector<T> &ref) {
    for (auto &d: ref) {
      if (!read_single(d)) return false;
    }
    return true;
  }
  template <class T, class U>
  bool read_single(pair<T, U> &p) {
    return (read_single(p.first) && read_single(p.second));
  }
  template <class A, class B, class C>
  bool read_single(tuple<A, B, C> &p) {
    return (read_single(get<0>(p)) && read_single(get<1>(p))
            && read_single(get<2>(p)));
  }
  template <class A, class B, class C, class D>
  bool read_single(tuple<A, B, C, D> &p) {
    return (read_single(get<0>(p)) && read_single(get<1>(p))
            && read_single(get<2>(p)) && read_single(get<3>(p)));
  }
  void read() {}
  template <class H, class... T>
  void read(H &h, T &... t) {
    bool f = read_single(h);
    assert(f);
    read(t...);
  }
  Scanner(FILE *fp) : fp(fp) {}
};

struct Printer {
  Printer(FILE *_fp) : fp(_fp) {}
  ~Printer() { flush(); }

  static constexpr size_t SIZE = 1 << 15;
  FILE *fp;
  char line[SIZE], small[50];
  size_t pos = 0;
  void flush() {
    fwrite(line, 1, pos, fp);
    pos = 0;
  }
  void write(const char &val) {
    if (pos == SIZE) flush();
    line[pos++] = val;
  }
  template <class T, enable_if_t<is_integral<T>::value, int> = 0>
  void write(T val) {
    if (pos > (1 << 15) - 50) flush();
    if (val == 0) {
      write('0');
      return;
    }
    if (val < 0) {
      write('-');
      val = -val; // todo min
    }
    size_t len = 0;
    while (val) {
      small[len++] = char(0x30 | (val % 10));
      val /= 10;
    }
    for (size_t i = 0; i < len; i++) { line[pos + i] = small[len - 1 - i]; }
    pos += len;
  }
  void write(const string &s) {
    for (char c: s) write(c);
  }
  void write(const char *s) {
    size_t len = strlen(s);
    for (size_t i = 0; i < len; i++) write(s[i]);
  }
  void write(const double &x) {
    ostringstream oss;
    oss << fixed << setprecision(15) << x;
    string s = oss.str();
    write(s);
  }
  void write(const long double &x) {
    ostringstream oss;
    oss << fixed << setprecision(15) << x;
    string s = oss.str();
    write(s);
  }
  template <class T, is_modint_t<T> * = nullptr>
  void write(T &ref) {
    write(ref.val);
  }
  template <class T>
  void write(const vector<T> &val) {
    auto n = val.size();
    for (size_t i = 0; i < n; i++) {
      if (i) write(' ');
      write(val[i]);
    }
  }
  template <class T, class U>
  void write(const pair<T, U> &val) {
    write(val.first);
    write(' ');
    write(val.second);
  }
  template <class A, class B, class C>
  void write(const tuple<A, B, C> &val) {
    auto &[a, b, c] = val;
    write(a), write(' '), write(b), write(' '), write(c);
  }
  template <class A, class B, class C, class D>
  void write(const tuple<A, B, C, D> &val) {
    auto &[a, b, c, d] = val;
    write(a), write(' '), write(b), write(' '), write(c), write(' '), write(d);
  }
  template <class A, class B, class C, class D, class E>
  void write(const tuple<A, B, C, D, E> &val) {
    auto &[a, b, c, d, e] = val;
    write(a), write(' '), write(b), write(' '), write(c), write(' '), write(d), write(' '), write(e);
  }
  template <class A, class B, class C, class D, class E, class F>
  void write(const tuple<A, B, C, D, E, F> &val) {
    auto &[a, b, c, d, e, f] = val;
    write(a), write(' '), write(b), write(' '), write(c), write(' '), write(d), write(' '), write(e), write(' '), write(f);
  }
  template <class T, size_t S>
  void write(const array<T, S> &val) {
    auto n = val.size();
    for (size_t i = 0; i < n; i++) {
      if (i) write(' ');
      write(val[i]);
    }
  }
  void write(i128 val) {
    string s;
    bool negative = 0;
    if(val < 0){
      negative = 1;
      val = -val;
    }
    while (val) {
      s += '0' + int(val % 10);
      val /= 10;
    }
    if(negative) s += "-";
    reverse(all(s));
    if (len(s) == 0) s = "0";
    write(s);
  }
};

Scanner scanner = Scanner(stdin);
Printer printer = Printer(stdout);

void flush() { printer.flush(); }
void print() { printer.write('\n'); }
template <class Head, class... Tail>
void print(Head &&head, Tail &&... tail) {
  printer.write(head);
  if (sizeof...(Tail)) printer.write(' ');
  print(forward<Tail>(tail)...);
}

void read() {}
template <class Head, class... Tail>
void read(Head &head, Tail &... tail) {
  scanner.read(head);
  read(tail...);
}

#define INT(...)   \
  int __VA_ARGS__; \
  read(__VA_ARGS__)
#define LL(...)   \
  ll __VA_ARGS__; \
  read(__VA_ARGS__)
#define STR(...)      \
  string __VA_ARGS__; \
  read(__VA_ARGS__)
#define CHAR(...)      \
  char __VA_ARGS__; \
  read(__VA_ARGS__)
#define DBL(...)      \
  double __VA_ARGS__; \
  read(__VA_ARGS__)

#define VEC(type, name, size) \
  vector<type> name(size);    \
  read(name)
#define VV(type, name, h, w)                     \
  vector<vector<type>> name(h, vector<type>(w)); \
  read(name)

void YES(bool t = 1) { print(t ? "YES" : "NO"); }
void NO(bool t = 1) { YES(!t); }
void Yes(bool t = 1) { print(t ? "Yes" : "No"); }
void No(bool t = 1) { Yes(!t); }
void yes(bool t = 1) { print(t ? "yes" : "no"); }
void no(bool t = 1) { yes(!t); }
#line 2 "library/alg/monoid/add.hpp"

template <typename E>
struct Monoid_Add {
  using X = E;
  using value_type = X;
  static constexpr X op(const X &x, const X &y) noexcept { return x + y; }
  static constexpr X inverse(const X &x) noexcept { return -x; }
  static constexpr X power(const X &x, ll n) noexcept { return X(n) * x; }
  static constexpr X unit() { return X(0); }
  static constexpr bool commute = true;
};
#line 2 "library/alg/monoid/max.hpp"
template <class X>
struct Monoid_Max {
  using value_type = X;
  static constexpr X op(const X &x, const X &y) noexcept { return max(x, y); }
  static constexpr X unit() { return numeric_limits<X>::lowest(); }
  static constexpr bool commute = true;
};
#line 3 "library/alg/lazy/max_add.hpp"

template <typename E>
struct Lazy_Max_Add {
  using MX = Monoid_Max<E>;
  using MA = Monoid_Add<E>;
  using X_structure = MX;
  using A_structure = MA;
  using X = typename MX::value_type;
  using A = typename MA::value_type;
  static constexpr X act(const X &x, const A &a) {
    if (x == numeric_limits<E>::lowest()) return x;
    return x + a;
  }
};
#line 1 "library/ds/bbst/rbst_lazy.hpp"
// reverse はとりあえず、Monoid の可換性を仮定している！
template <typename Lazy, int NODES = 1'000'000>
struct RBST_Lazy {
  using Monoid_X = typename Lazy::X_structure;
  using Monoid_A = typename Lazy::A_structure;
  using X = typename Monoid_X::value_type;
  using A = typename Monoid_A::value_type;

  struct Node {
    Node *l, *r;
    X x, prod;
    A lazy; // lazy は x, prod に反映済
    u32 size;
    bool rev;
  };

  Node *pool;
  int pid;
  using np = Node *;

  RBST_Lazy() : pid(0) { pool = new Node[NODES]; }

  void reset() { pid = 0; }

  np new_node(const X &x) {
    pool[pid].l = pool[pid].r = nullptr;
    pool[pid].x = x;
    pool[pid].prod = x;
    pool[pid].lazy = Monoid_A::unit();
    pool[pid].size = 1;
    pool[pid].rev = 0;
    return &(pool[pid++]);
  }

  np new_node(const vc<X> &dat) {
    auto dfs = [&](auto &dfs, u32 l, u32 r) -> np {
      if (l == r) return nullptr;
      if (r == l + 1) return new_node(dat[l]);
      u32 m = (l + r) / 2;
      np l_root = dfs(dfs, l, m);
      np r_root = dfs(dfs, m + 1, r);
      np root = new_node(dat[m]);
      root->l = l_root, root->r = r_root;
      update(root);
      return root;
    };
    return dfs(dfs, 0, len(dat));
  }

  np merge(np l_root, np r_root) { return merge_rec(l_root, r_root); }
  np merge3(np a, np b, np c) { return merge(merge(a, b), c); }
  np merge4(np a, np b, np c, np d) { return merge(merge(merge(a, b), c), d); }
  pair<np, np> split(np root, u32 k) {
    if (!root) {
      assert(k == 0);
      return {nullptr, nullptr};
    }
    assert(0 <= k && k <= root->size);
    return split_rec(root, k);
  }
  tuple<np, np, np> split3(np root, u32 l, u32 r) {
    np nm, nr;
    tie(root, nr) = split(root, r);
    tie(root, nm) = split(root, l);
    return {root, nm, nr};
  }
  tuple<np, np, np, np> split4(np root, u32 i, u32 j, u32 k) {
    np d;
    tie(root, d) = split(root, k);
    auto [a, b, c] = split3(root, i, j);
    return {a, b, c, d};
  }

  X prod(np root, u32 l, u32 r) {
    if (l == r) return Monoid_X::unit();
    return prod_rec(root, l, r);
  }

  np reverse(np root, u32 l, u32 r) {
    assert(Monoid_X::commute);
    assert(0 <= l && l <= r && r <= root->size);
    if (r - l <= 1) return root;
    auto [nl, nm, nr] = split3(root, l, r);
    nm->rev ^= 1;
    return merge3(nl, nm, nr);
  }

  Node *apply(Node *root, u32 l, u32 r, const A a) {
    assert(0 <= l && l <= r && r <= root->size);
    return apply_rec(root, l, r, a);
  }

  Node *set(Node *root, u32 k, const X &x) { return set_rec(root, k, x); }
  Node *multiply(Node *root, u32 k, const X &x) {
    return multiply_rec(root, k, x);
  }
  X get(Node *root, u32 k) { return get_rec(root, k); }

  vc<X> get_all(Node *root) {
    vc<X> res;
    auto dfs = [&](auto &dfs, Node *root, bool rev, A lazy) -> void {
      if (!root) return;
      rev ^= root->rev;
      X me = Lazy::act(root->x, lazy);
      lazy = Monoid_A::op(root->lazy, lazy);
      dfs(dfs, (rev ? root->r : root->l), rev, lazy);
      res.eb(me);
      dfs(dfs, (rev ? root->l : root->r), rev, lazy);
    };
    dfs(dfs, root, 0, Monoid_A::unit());
    return res;
  }

  template <typename F>
  u32 max_right(Node *root, const F check, int L) {
    assert(check(Monoid_X::unit()));
    X x = Monoid_X::unit();
    return max_right_rec(root, check, L, x);
  }

private:
  inline u32 xor128() {
    static u32 x = 123456789;
    static u32 y = 362436069;
    static u32 z = 521288629;
    static u32 w = 88675123;
    u32 t = x ^ (x << 11);
    x = y;
    y = z;
    z = w;
    return w = (w ^ (w >> 19)) ^ (t ^ (t >> 8));
  }

  void prop(Node *c) {
    if (c->lazy != Monoid_A::unit()) {
      if (c->l) {
        c->l->x = Lazy::act(c->l->x, c->lazy);
        c->l->prod = Lazy::act(c->l->prod, c->lazy);
        c->l->lazy = Monoid_A::op(c->l->lazy, c->lazy);
      }
      if (c->r) {
        c->r->x = Lazy::act(c->r->x, c->lazy);
        c->r->prod = Lazy::act(c->r->prod, c->lazy);
        c->r->lazy = Monoid_A::op(c->r->lazy, c->lazy);
      }
      c->lazy = Monoid_A::unit();
    }
    if (c->rev) {
      swap(c->l, c->r);
      if (c->l) c->l->rev ^= 1;
      if (c->r) c->r->rev ^= 1;
      c->rev = 0;
    }
  }

  void update(Node *c) {
    c->size = 1;
    c->prod = c->x;
    if (c->l) {
      c->size += c->l->size;
      c->prod = Monoid_X::op(c->l->prod, c->prod);
    }
    if (c->r) {
      c->size += c->r->size;
      c->prod = Monoid_X::op(c->prod, c->r->prod);
    }
  }

  Node *merge_rec(Node *l_root, Node *r_root) {
    if (!l_root) return r_root;
    if (!r_root) return l_root;
    u32 sl = l_root->size, sr = r_root->size;
    if (xor128() % (sl + sr) < sl) {
      prop(l_root);
      l_root->r = merge_rec(l_root->r, r_root);
      update(l_root);
      return l_root;
    }
    prop(r_root);
    r_root->l = merge_rec(l_root, r_root->l);
    update(r_root);
    return r_root;
  }

  pair<Node *, Node *> split_rec(Node *root, u32 k) {
    if (!root) return {nullptr, nullptr};
    prop(root);
    u32 sl = (root->l ? root->l->size : 0);
    if (k <= sl) {
      auto [nl, nr] = split_rec(root->l, k);
      root->l = nr;
      update(root);
      return {nl, root};
    }
    auto [nl, nr] = split_rec(root->r, k - (1 + sl));
    root->r = nl;
    update(root);
    return {root, nr};
  }

  Node *set_rec(Node *root, u32 k, const X &x) {
    if (!root) return root;
    prop(root);
    u32 sl = (root->l ? root->l->size : 0);
    if (k < sl) {
      root->l = set_rec(root->l, k, x);
      update(root);
      return root;
    }
    if (k == sl) {
      root->x = x;
      update(root);
      return root;
    }
    root->r = set_rec(root->r, k - (1 + sl), x);
    update(root);
    return root;
  }

  Node *multiply_rec(Node *root, u32 k, const X &x) {
    if (!root) return root;
    prop(root);
    u32 sl = (root->l ? root->l->size : 0);
    if (k < sl) {
      root->l = multiply_rec(root->l, k, x);
      update(root);
      return root;
    }
    if (k == sl) {
      root->x = Monoid_X::op(root->x, x);
      update(root);
      return root;
    }
    root->r = multiply_rec(root->r, k - (1 + sl), x);
    update(root);
    return root;
  }

  X prod_rec(Node *root, u32 l, u32 r) {
    if (l == 0 && r == root->size) { return root->prod; }
    prop(root);
    u32 sl = (root->l ? root->l->size : 0);
    X res = Monoid_X::unit();
    if (l < sl) { res = Monoid_X::op(res, prod_rec(root->l, l, min(r, sl))); }
    if (l <= sl && sl < r) res = Monoid_X::op(res, root->x);
    u32 k = 1 + sl;
    if (k < r) res = Monoid_X::op(res, prod_rec(root->r, max(k, l) - k, r - k));
    return res;
  }

  X get_rec(Node *root, u32 k) {
    prop(root);
    u32 sl = (root->l ? root->l->size : 0);
    if (k < sl) return get_rec(root->l, k);
    if (k == sl) return root->x;
    return get_rec(root->r, k - (1 + sl));
  }

  Node *apply_rec(Node *root, u32 l, u32 r, const A &a) {
    prop(root);
    if (l == 0 && r == root->size) {
      root->x = Lazy::act(root->x, a);
      root->prod = Lazy::act(root->prod, a);
      root->lazy = a;
      return root;
    }
    u32 sl = (root->l ? root->l->size : 0);
    if (l < sl) apply_rec(root->l, l, min(r, sl), a);
    if (l <= sl && sl < r) root->x = Lazy::act(root->x, a);
    u32 k = 1 + sl;
    if (k < r) apply_rec(root->r, max(k, l) - k, r - k, a);
    update(root);
    return root;
  }

  template <typename F>
  u32 max_right_rec(Node *n, const F check, u32 L, X &x) {
    if (!n) return 0;
    if (L == 0) {
      X y = Monoid_X::op(x, n->prod);
      if (check(y)) {
        x = y;
        return n->size;
      }
    }
    u32 sl = (n->l ? n->l->size : 0);
    if (L < sl) {
      u32 k = max_right_rec(n->l, check, L, x);
      if (k < sl) return k;
    }
    if (L <= sl) {
      X y = Monoid_X::op(x, n->x);
      if (!check(y)) { return sl; }
      x = y;
    }
    L = (L > sl ? L - (1 + sl) : 0);
    return (1 + sl) + max_right_rec(n->r, check, L, x);
  }
};
#line 6 "main.cpp"

void solve() {
  LL(N);
  ll LIM = 100'010;
  using Lazy = Lazy_Max_Add<int>;
  vc<int> dp(LIM);
  RBST_Lazy<Lazy> seg;
  auto root = seg.new_node(dp);

  FOR(N) {
    LL(L, R);
    {
      int a = seg.prod(root, R, R + 1);
      int b = seg.prod(root, R - 1, R);
      if (a != b) {
        --R;
      } else {
        auto check = [&](int e) -> bool { return e <= a; };
        int k = seg.max_right(root, check, R);
        R = k - 1;
      }
    }
    if (L > R) continue;
    root = seg.apply(root, L, R, 1);
    int x = seg.get(root, L - 1);
    auto [a, b, c, d] = seg.split4(root, L, R, R + 1);
    root = seg.merge4(a, seg.new_node(x + 1), b, d);
    assert(root->size == LIM);
  }

  print(seg.prod(root, 0, LIM));
}

signed main() {
  cin.tie(nullptr);
  ios::sync_with_stdio(false);
  cout << setprecision(15);

  ll T = 1;
  // LL(T);
  FOR(T) solve();

  return 0;
}