Problem p03421 (C++)

Buggy submission (status: Time Limit Exceeded):
#line 2 "header.hpp"

//%snippet.set('header')%
//%snippet.fold()%
#ifndef HEADER_H
#define HEADER_H

// template version 2.0
using namespace std;
#include <bits/stdc++.h>

// varibable settings
const long long INF = 1e18;
template <class T> constexpr T inf = numeric_limits<T>::max() / 2.1;

#define _overload3(_1, _2, _3, name, ...) name
#define _rep(i, n) repi(i, 0, n)
#define repi(i, a, b) for (ll i = (ll)(a); i < (ll)(b); ++i)
#define rep(...) _overload3(__VA_ARGS__, repi, _rep, )(__VA_ARGS__)
#define _rrep(i, n) rrepi(i, 0, n)
#define rrepi(i, a, b) for (ll i = (ll)((b)-1); i >= (ll)(a); --i)
#define r_rep(...) _overload3(__VA_ARGS__, rrepi, _rrep, )(__VA_ARGS__)
#define each(i, a) for (auto &&i : a)
#define all(x) (x).begin(), (x).end()
#define sz(x) ((int)(x).size())
#define pb(a) push_back(a)
#define mp(a, b) make_pair(a, b)
#define mt(...) make_tuple(__VA_ARGS__)
#define ub upper_bound
#define lb lower_bound
#define lpos(A, x) (lower_bound(all(A), x) - A.begin())
#define upos(A, x) (upper_bound(all(A), x) - A.begin())
template <class T, class U> inline void chmax(T &a, const U &b) {
  if ((a) < (b))
    (a) = (b);
}
template <class T, class U> inline void chmin(T &a, const U &b) {
  if ((a) > (b))
    (a) = (b);
}
template <typename X, typename T> auto make_table(X x, T a) {
  return vector<T>(x, a);
}
template <typename X, typename Y, typename Z, typename... Zs>
auto make_table(X x, Y y, Z z, Zs... zs) {
  auto cont = make_table(y, z, zs...);
  return vector<decltype(cont)>(x, cont);
}

#define cdiv(a, b) (((a) + (b)-1) / (b))
#define is_in(x, a, b) ((a) <= (x) && (x) < (b))
#define uni(x)                                                                 \
  sort(all(x));                                                                \
  x.erase(unique(all(x)), x.end())
#define slice(l, r) substr(l, r - l)

typedef long long ll;
typedef long double ld;
using vl = vector<ll>;
using vvl = vector<vl>;
using pll = pair<ll, ll>;

template <typename T> using PQ = priority_queue<T, vector<T>, greater<T>>;
void check_input() {
  assert(cin.eof() == 0);
  int tmp;
  cin >> tmp;
  assert(cin.eof() == 1);
}

#if defined(PCM) || defined(LOCAL)
#else
#define dump(...) ;
#define dump_1d(...) ;
#define dump_2d(...) ;
#define cerrendl ;
#endif

#endif /* HEADER_H */
//%snippet.end()%
#line 2 "solve.cpp"
template <class T = ll> using vec = vector<T>;
struct Fast {
  Fast() {
    std::cin.tie(0);
    ios::sync_with_stdio(false);
  }
} fast;

struct zipper { /*{{{*/
  // unordered_map<long long, int> zip_map;  // [2:0, 3:1, 5:2, 10:3]
  // debugしづらい
  map<long long, int> zip_map; // [2:0, 3:1, 5:2, 10:3]
  vector<long long> _unzipper; // [2, 3, 5, 10]
  bool _is_build = false;
  int n = 0;

  zipper(long long inf_value = INF) { /*{{{*/
    _unzipper.push_back(-inf_value);
    _unzipper.push_back(inf_value);
  }                                                        /*}}}*/
  zipper(vector<long long> a, long long inf_value = INF) { /*{{{*/
    _unzipper = vector<long long>(sz(a));
    rep(i, sz(a)) { _unzipper[i] = a[i]; }
    _unzipper.push_back(-inf_value);
    _unzipper.push_back(inf_value);
    build();
  }                              /*}}}*/
  void add_value(long long lv) { /*{{{*/
    _unzipper.push_back(lv);
    _is_build = false;
  }              /*}}}*/
  void build() { /*{{{*/
    uni(_unzipper);
    zip_map.clear();
    n = sz(_unzipper);
    rep(i, n) { zip_map[_unzipper[i]] = i; }
    _is_build = true;
  }                                        /*}}}*/
  vector<int> zip(vector<long long> lvs) { /*{{{*/
    if (!_is_build)
      assert(false);
    int n = sz(lvs);
    vector<int> res(n);
    rep(i, n) res[i] = zip_map[lvs[i]];
    return res;
  }                       /*}}}*/
  int zip(long long lv) { /*{{{*/
    if (!_is_build)
      assert(false);
    return zip_map[lv];
  } /*}}}*/
  int operator()(long long lv) { return zip(lv); }

  long long unzip(int sv) { /*{{{*/
    if (!_is_build)
      assert(false);
    return _unzipper[sv];
  } /*}}}*/
  int operator[](int sv) { return unzip(sv); }

  int size() { return n; }

#if defined(PCM) || defined(LOCAL) /*{{{*/
  friend ostream &operator<<(ostream &os, const zipper &zp) {
    os << endl;
    os << "_is_build: " << zp._is_build << endl;
    os << "zip_map:   " << zp.zip_map << endl;
    os << "_unzipper:   " << zp._unzipper << endl;
    return os;
  }
#endif /*}}}*/
};     /*}}}*/
// How to use {{{
// construct
// auto z = zipper(x); // x: vector<long long>;
// auto z = zipper(x, 30*INF);

// auto z = zipper();
// auto z = zipper();
// z.add_value(3);
// z.add_value(5);
// z.add_value(10);
// z.add_value(100000000);
// z.build();

// other method
// z(x[i]); -> zipped x[i]
// z.unzip(z(x[i])) -> x[i];
// z.get_zipped(x) -> zipped x
// }}}

template <class T> int lis(const vector<T> &x, bool strict = true) { /*{{{*/
  int n = sz(x);
  vector<T> dp(n + 1, numeric_limits<T>().max());
  vector<pair<int, T>> update_info(n);
  dp[0] = numeric_limits<T>().min();
  int res = 0;
  rep(i, n) {
    int j;
    if (strict)
      j = lb(all(dp), x[i]) - dp.begin();
    else
      j = ub(all(dp), x[i]) - dp.begin();
    chmax(res, j);
    update_info[i] = make_pair(j, dp[j]);
    dp[j] = x[i];
  }

  // 復元
  int now_len = res;
  vector<T> lis;
  r_rep(i, n) {
    auto [j, pre] = update_info[i];
    if (j == now_len) {
      now_len--;
      lis.push_back(x[i]);
    }
    dp[j] = pre;
  }
  assert(now_len == 0);
  reverse(all(lis));

  return res;
} /*}}}*/

int solve() {
  ll n, a, b;
  cin >> n >> a >> b;

  if (a + b > n + 1 || a * b < n) {
    cout << -1 << endl;
    return 0;
  }

  ll m = a * b;

  vec<ll> res;
  ll d = n - (a + b - 1);
  rep(i, 1, b + 1) {
    // [m - (i*a) + 1, m - ((i-1)*a + 1)]
    for (ll j = m - (i * a) + 1; j <= m - (i - 1) * a; j++) {
      if (i == 1 || j == m - (i * a) + 1) {
        res.pb(j);
      } else if (d > 0) {
        res.pb(j);
        d--;
      }
    }
  }
  dump(res);
  auto z = zipper(res);
  auto ans = z.zip(res);
  dump(ans);

  ll x = lis(ans);
  auto rp = ans;
  reverse(all(rp));
  ll y = lis(rp);
  dump(x, y);
  assert(a == x && b == y);

  rep(i, sz(ans)) cout << ans[i] << (i != sz(ans) - 1 ? " " : "\n");

  return 0;
}

int main() { /*{{{*/
  solve();
  check_input();
  return 0;
} /*}}}*/


Fixed submission:
#line 2 "header.hpp"

//%snippet.set('header')%
//%snippet.fold()%
#ifndef HEADER_H
#define HEADER_H

// template version 2.0
using namespace std;
#include <bits/stdc++.h>

// varibable settings
const long long INF = 1e18;
template <class T> constexpr T inf = numeric_limits<T>::max() / 2.1;

#define _overload3(_1, _2, _3, name, ...) name
#define _rep(i, n) repi(i, 0, n)
#define repi(i, a, b) for (ll i = (ll)(a); i < (ll)(b); ++i)
#define rep(...) _overload3(__VA_ARGS__, repi, _rep, )(__VA_ARGS__)
#define _rrep(i, n) rrepi(i, 0, n)
#define rrepi(i, a, b) for (ll i = (ll)((b)-1); i >= (ll)(a); --i)
#define r_rep(...) _overload3(__VA_ARGS__, rrepi, _rrep, )(__VA_ARGS__)
#define each(i, a) for (auto &&i : a)
#define all(x) (x).begin(), (x).end()
#define sz(x) ((int)(x).size())
#define pb(a) push_back(a)
#define mp(a, b) make_pair(a, b)
#define mt(...) make_tuple(__VA_ARGS__)
#define ub upper_bound
#define lb lower_bound
#define lpos(A, x) (lower_bound(all(A), x) - A.begin())
#define upos(A, x) (upper_bound(all(A), x) - A.begin())
template <class T, class U> inline void chmax(T &a, const U &b) {
  if ((a) < (b))
    (a) = (b);
}
template <class T, class U> inline void chmin(T &a, const U &b) {
  if ((a) > (b))
    (a) = (b);
}
template <typename X, typename T> auto make_table(X x, T a) {
  return vector<T>(x, a);
}
template <typename X, typename Y, typename Z, typename... Zs>
auto make_table(X x, Y y, Z z, Zs... zs) {
  auto cont = make_table(y, z, zs...);
  return vector<decltype(cont)>(x, cont);
}

#define cdiv(a, b) (((a) + (b)-1) / (b))
#define is_in(x, a, b) ((a) <= (x) && (x) < (b))
#define uni(x)                                                                 \
  sort(all(x));                                                                \
  x.erase(unique(all(x)), x.end())
#define slice(l, r) substr(l, r - l)

typedef long long ll;
typedef long double ld;
using vl = vector<ll>;
using vvl = vector<vl>;
using pll = pair<ll, ll>;

template <typename T> using PQ = priority_queue<T, vector<T>, greater<T>>;
void check_input() {
  assert(cin.eof() == 0);
  int tmp;
  cin >> tmp;
  assert(cin.eof() == 1);
}

#if defined(PCM) || defined(LOCAL)
#else
#define dump(...) ;
#define dump_1d(...) ;
#define dump_2d(...) ;
#define cerrendl ;
#endif

#endif /* HEADER_H */
//%snippet.end()%
#line 2 "solve.cpp"
template <class T = ll> using vec = vector<T>;
struct Fast {
  Fast() {
    std::cin.tie(0);
    ios::sync_with_stdio(false);
  }
} fast;

struct zipper { /*{{{*/
  // unordered_map<long long, int> zip_map;  // [2:0, 3:1, 5:2, 10:3]
  // debugしづらい
  map<long long, int> zip_map; // [2:0, 3:1, 5:2, 10:3]
  vector<long long> _unzipper; // [2, 3, 5, 10]
  bool _is_build = false;
  int n = 0;

  zipper(long long inf_value = INF) { /*{{{*/
    _unzipper.push_back(-inf_value);
    _unzipper.push_back(inf_value);
  }                                                        /*}}}*/
  zipper(vector<long long> a, long long inf_value = INF) { /*{{{*/
    _unzipper = vector<long long>(sz(a));
    rep(i, sz(a)) { _unzipper[i] = a[i]; }
    _unzipper.push_back(-inf_value);
    _unzipper.push_back(inf_value);
    build();
  }                              /*}}}*/
  void add_value(long long lv) { /*{{{*/
    _unzipper.push_back(lv);
    _is_build = false;
  }              /*}}}*/
  void build() { /*{{{*/
    uni(_unzipper);
    zip_map.clear();
    n = sz(_unzipper);
    rep(i, n) { zip_map[_unzipper[i]] = i; }
    _is_build = true;
  }                                        /*}}}*/
  vector<int> zip(vector<long long> lvs) { /*{{{*/
    if (!_is_build)
      assert(false);
    int n = sz(lvs);
    vector<int> res(n);
    rep(i, n) res[i] = zip_map[lvs[i]];
    return res;
  }                       /*}}}*/
  int zip(long long lv) { /*{{{*/
    if (!_is_build)
      assert(false);
    return zip_map[lv];
  } /*}}}*/
  int operator()(long long lv) { return zip(lv); }

  long long unzip(int sv) { /*{{{*/
    if (!_is_build)
      assert(false);
    return _unzipper[sv];
  } /*}}}*/
  int operator[](int sv) { return unzip(sv); }

  int size() { return n; }

#if defined(PCM) || defined(LOCAL) /*{{{*/
  friend ostream &operator<<(ostream &os, const zipper &zp) {
    os << endl;
    os << "_is_build: " << zp._is_build << endl;
    os << "zip_map:   " << zp.zip_map << endl;
    os << "_unzipper:   " << zp._unzipper << endl;
    return os;
  }
#endif /*}}}*/
};     /*}}}*/
// How to use {{{
// construct
// auto z = zipper(x); // x: vector<long long>;
// auto z = zipper(x, 30*INF);

// auto z = zipper();
// auto z = zipper();
// z.add_value(3);
// z.add_value(5);
// z.add_value(10);
// z.add_value(100000000);
// z.build();

// other method
// z(x[i]); -> zipped x[i]
// z.unzip(z(x[i])) -> x[i];
// z.get_zipped(x) -> zipped x
// }}}

template <class T> int lis(const vector<T> &x, bool strict = true) { /*{{{*/
  int n = sz(x);
  vector<T> dp(n + 1, numeric_limits<T>().max());
  vector<pair<int, T>> update_info(n);
  dp[0] = numeric_limits<T>().min();
  int res = 0;
  rep(i, n) {
    int j;
    if (strict)
      j = lb(all(dp), x[i]) - dp.begin();
    else
      j = ub(all(dp), x[i]) - dp.begin();
    chmax(res, j);
    update_info[i] = make_pair(j, dp[j]);
    dp[j] = x[i];
  }

  // 復元
  int now_len = res;
  vector<T> lis;
  r_rep(i, n) {
    auto [j, pre] = update_info[i];
    if (j == now_len) {
      now_len--;
      lis.push_back(x[i]);
    }
    dp[j] = pre;
  }
  assert(now_len == 0);
  reverse(all(lis));

  return res;
} /*}}}*/

int solve() {
  ll n, a, b;
  cin >> n >> a >> b;

  if (a + b > n + 1 || a * b < n) {
    cout << -1 << endl;
    return 0;
  }

  ll m = a * b;

  vec<ll> res;
  ll d = n - (a + b - 1);
  rep(i, 1, b + 1) {
    // [m - (i*a) + 1, m - ((i-1)*a + 1)]
    for (ll j = m - (i * a) + 1; j <= m - (i - 1) * a; j++) {
      if (i == 1 || j == m - (i * a) + 1) {
        res.pb(j);
      } else if (d > 0) {
        res.pb(j);
        d--;
      } else {
        break;
      }
    }
  }
  dump(res);
  auto z = zipper(res);
  auto ans = z.zip(res);
  dump(ans);

  ll x = lis(ans);
  auto rp = ans;
  reverse(all(rp));
  ll y = lis(rp);
  dump(x, y);
  assert(a == x && b == y);

  rep(i, sz(ans)) cout << ans[i] << (i != sz(ans) - 1 ? " " : "\n");

  return 0;
}

int main() { /*{{{*/
  solve();
  check_input();
  return 0;
} /*}}}*/