Problem p02551 (C++) — buggy submission, verdict: Time Limit Exceeded

#ifdef LOCAL
#define _GLIBCXX_DEBUG
#define __clock__
#else
#pragma GCC optimize("Ofast")
#endif
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ld = long double;
using VI = vector<ll>;
using VV = vector<VI>;
using VS = vector<string>;
using PII = pair<ll, ll>;

// tourist set
template <typename A, typename B> string to_string(pair<A, B> p);

template <typename A, typename B, typename C>
string to_string(tuple<A, B, C> p);

template <typename A, typename B, typename C, typename D>
string to_string(tuple<A, B, C, D> p);

string to_string(const string &s) { return '"' + s + '"'; }

string to_string(const char *s) { return to_string((string)s); }

string to_string(bool b) { return (b ? "true" : "false"); }

string to_string(vector<bool> v) {
  bool first = true;
  string res = "{";
  for (int i = 0; i < static_cast<int>(v.size()); i++) {
    if (!first) {
      res += ", ";
    }
    first = false;
    res += to_string(v[i]);
  }
  res += "}";
  return res;
}

template <size_t N> string to_string(bitset<N> v) {
  string res = "";
  for (size_t i = 0; i < N; i++) {
    res += static_cast<char>('0' + v[i]);
  }
  return res;
}

template <typename A> string to_string(A v) {
  bool first = true;
  string res = "{";
  for (const auto &x : v) {
    if (!first) {
      res += ", ";
    }
    first = false;
    res += to_string(x);
  }
  res += "}";
  return res;
}

template <typename A, typename B> string to_string(pair<A, B> p) {
  return "(" + to_string(p.first) + ", " + to_string(p.second) + ")";
}

template <typename A, typename B, typename C>
string to_string(tuple<A, B, C> p) {
  return "(" + to_string(get<0>(p)) + ", " + to_string(get<1>(p)) + ", " +
         to_string(get<2>(p)) + ")";
}

template <typename A, typename B, typename C, typename D>
string to_string(tuple<A, B, C, D> p) {
  return "(" + to_string(get<0>(p)) + ", " + to_string(get<1>(p)) + ", " +
         to_string(get<2>(p)) + ", " + to_string(get<3>(p)) + ")";
}

void debug_out() { cerr << '\\n'; }

template <typename Head, typename... Tail> void debug_out(Head H, Tail... T) {
  cerr << " " << to_string(H);
  debug_out(T...);
}

#ifdef LOCAL
#define debug(...) cerr << "[" << #__VA_ARGS__ << "]:", debug_out(__VA_ARGS__)
#else
#define debug(...) 42
#endif
// tourist set end

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

#define FOR(i, a, b) for (ll i = (a); i < (b); ++i)
#define rep(i, b) FOR(i, 0, b)
#define ALL(v) (v).begin(), (v).end()
#define p(s) cout << (s) << '\\n'
#define p2(s, t) cout << (s) << " " << (t) << '\\n'
#define br() p("")
#define pn(s) cout << (#s) << " " << (s) << '\\n'
#define SZ(x) ((int)(x).size())
#define SORT(A) sort(ALL(A))
#define RSORT(A) sort(ALL(A), greater<ll>())
#define MP make_pair
#define p_yes() p("YES")
#define p_no() p("NO")
#define possible() p("Possible")
#define impossible() p("Impossible")

ll SUM(VI &V) { return accumulate(ALL(V), 0LL); }

ll MIN(VI &V) { return *min_element(ALL(V)); }
ll MAX(VI &V) { return *max_element(ALL(V)); }

void print_vector(VI &V) {
  ll n = V.size();
  rep(i, n) {
    if (i)
      cout << ' ';
    cout << V[i];
  }
  cout << endl;
}

ll gcd(ll a, ll b) {
  if (b == 0)
    return a;
  return gcd(b, a % b);
}

ll lcm(ll a, ll b) {
  ll g = gcd(a, b);
  return a / g * b;
}

// long double
using ld = long double;
#define EPS (1e-14)
#define equals(a, b) (fabs((a) - (b)) < EPS)

void no() {
  p_no();
  exit(0);
}
void yes() {
  p_yes();
  exit(0);
}

const ll mod = 1e9 + 7;
const ll inf = 1e18;
const double PI = acos(-1);

// snuke's mint
// auto mod int
// https://youtu.be/L8grWxBlIZ4?t=9858
// https://youtu.be/ERZuLAxZffQ?t=4807 : optimize
// https://youtu.be/8uowVvQ_-Mo?t=1329 : division
// const int mod = 1000000007;
struct mint {
  ll x; // typedef long long ll;
  mint(ll x = 0) : x((x % mod + mod) % mod) {}
  mint operator-() const { return mint(-x); }
  mint &operator+=(const mint a) {
    if ((x += a.x) >= mod)
      x -= mod;
    return *this;
  }
  mint &operator-=(const mint a) {
    if ((x += mod - a.x) >= mod)
      x -= mod;
    return *this;
  }
  mint &operator*=(const mint a) {
    (x *= a.x) %= mod;
    return *this;
  }
  mint operator+(const mint a) const {
    mint res(*this);
    return res += a;
  }
  mint operator-(const mint a) const {
    mint res(*this);
    return res -= a;
  }
  mint operator*(const mint a) const {
    mint res(*this);
    return res *= a;
  }
  mint pow(ll t) const {
    if (!t)
      return 1;
    mint a = pow(t >> 1);
    a *= a;
    if (t & 1)
      a *= *this;
    return a;
  }

  // for prime mod
  mint inv() const { return pow(mod - 2); }
  mint &operator/=(const mint a) { return (*this) *= a.inv(); }
  mint operator/(const mint a) const {
    mint res(*this);
    return res /= a;
  }
};

#include <algorithm>

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

namespace atcoder {

namespace internal {

// @param n `0 <= n`
// @return minimum non-negative `x` s.t. `n <= 2**x`
int ceil_pow2(int n) {
  int x = 0;
  while ((1U << x) < (unsigned int)(n))
    x++;
  return x;
}

// @param n `1 <= n`
// @return minimum non-negative `x` s.t. `(n & (1 << x)) != 0`
int bsf(unsigned int n) {
#ifdef _MSC_VER
  unsigned long index;
  _BitScanForward(&index, n);
  return index;
#else
  return __builtin_ctz(n);
#endif
}

} // namespace internal

} // namespace atcoder

#include <cassert>
#include <iostream>
#include <vector>
namespace atcoder {

template <class S, S (*op)(S, S), S (*e)(), class F, S (*mapping)(F, S),
          F (*composition)(F, F), F (*id)()>
struct lazy_segtree {
public:
  lazy_segtree() : lazy_segtree(0) {}
  lazy_segtree(int n) : lazy_segtree(std::vector<S>(n, e())) {}
  lazy_segtree(const std::vector<S> &v) : _n(int(v.size())) {
    log = internal::ceil_pow2(_n);
    size = 1 << log;
    d = std::vector<S>(2 * size, e());
    lz = std::vector<F>(size, id());
    for (int i = 0; i < _n; i++)
      d[size + i] = v[i];
    for (int i = size - 1; i >= 1; i--) {
      update(i);
    }
  }

  void set(int p, S x) {
    assert(0 <= p && p < _n);
    p += size;
    for (int i = log; i >= 1; i--)
      push(p >> i);
    d[p] = x;
    for (int i = 1; i <= log; i++)
      update(p >> i);
  }

  S get(int p) {
    assert(0 <= p && p < _n);
    p += size;
    for (int i = log; i >= 1; i--)
      push(p >> i);
    return d[p];
  }

  S prod(int l, int r) {
    assert(0 <= l && l <= r && r <= _n);
    if (l == r)
      return e();

    l += size;
    r += size;

    for (int i = log; i >= 1; i--) {
      if (((l >> i) << i) != l)
        push(l >> i);
      if (((r >> i) << i) != r)
        push(r >> i);
    }

    S sml = e(), smr = e();
    while (l < r) {
      if (l & 1)
        sml = op(sml, d[l++]);
      if (r & 1)
        smr = op(d[--r], smr);
      l >>= 1;
      r >>= 1;
    }

    return op(sml, smr);
  }

  S all_prod() { return d[1]; }

  void apply(int p, F f) {
    assert(0 <= p && p < _n);
    p += size;
    for (int i = log; i >= 1; i--)
      push(p >> i);
    d[p] = mapping(f, d[p]);
    for (int i = 1; i <= log; i++)
      update(p >> i);
  }
  void apply(int l, int r, F f) {
    assert(0 <= l && l <= r && r <= _n);
    if (l == r)
      return;

    l += size;
    r += size;

    for (int i = log; i >= 1; i--) {
      if (((l >> i) << i) != l)
        push(l >> i);
      if (((r >> i) << i) != r)
        push((r - 1) >> i);
    }

    {
      int l2 = l, r2 = r;
      while (l < r) {
        if (l & 1)
          all_apply(l++, f);
        if (r & 1)
          all_apply(--r, f);
        l >>= 1;
        r >>= 1;
      }
      l = l2;
      r = r2;
    }

    for (int i = 1; i <= log; i++) {
      if (((l >> i) << i) != l)
        update(l >> i);
      if (((r >> i) << i) != r)
        update((r - 1) >> i);
    }
  }

  template <bool (*g)(S)> int max_right(int l) {
    return max_right(l, [](S x) { return g(x); });
  }
  template <class G> int max_right(int l, G g) {
    assert(0 <= l && l <= _n);
    assert(g(e()));
    if (l == _n)
      return _n;
    l += size;
    for (int i = log; i >= 1; i--)
      push(l >> i);
    S sm = e();
    do {
      while (l % 2 == 0)
        l >>= 1;
      if (!g(op(sm, d[l]))) {
        while (l < size) {
          push(l);
          l = (2 * l);
          if (g(op(sm, d[l]))) {
            sm = op(sm, d[l]);
            l++;
          }
        }
        return l - size;
      }
      sm = op(sm, d[l]);
      l++;
    } while ((l & -l) != l);
    return _n;
  }

  template <bool (*g)(S)> int min_left(int r) {
    return min_left(r, [](S x) { return g(x); });
  }
  template <class G> int min_left(int r, G g) {
    assert(0 <= r && r <= _n);
    assert(g(e()));
    if (r == 0)
      return 0;
    r += size;
    for (int i = log; i >= 1; i--)
      push((r - 1) >> i);
    S sm = e();
    do {
      r--;
      while (r > 1 && (r % 2))
        r >>= 1;
      if (!g(op(d[r], sm))) {
        while (r < size) {
          push(r);
          r = (2 * r + 1);
          if (g(op(d[r], sm))) {
            sm = op(d[r], sm);
            r--;
          }
        }
        return r + 1 - size;
      }
      sm = op(d[r], sm);
    } while ((r & -r) != r);
    return 0;
  }

private:
  int _n, size, log;
  std::vector<S> d;
  std::vector<F> lz;

  void update(int k) { d[k] = op(d[2 * k], d[2 * k + 1]); }
  void all_apply(int k, F f) {
    d[k] = mapping(f, d[k]);
    if (k < size)
      lz[k] = composition(f, lz[k]);
  }
  void push(int k) {
    all_apply(2 * k, lz[k]);
    all_apply(2 * k + 1, lz[k]);
    lz[k] = id();
  }
};

} // namespace atcoder

using namespace atcoder; // 忘れがち

struct S {
  ll a;
  int size;
};

struct F {
  ll a, b;
};

S op(S l, S r) { return S{l.a + r.a, l.size + r.size}; }

S e() { return S{0, 0}; }

S mapping(F l, S r) { return S{r.a * l.a + r.size * l.b, r.size}; }

F composition(F l, F r) { return F{r.a * l.a, r.b * l.a + l.b}; }

F id() { return F{1, 0}; }

int main() {
  cin.tie(0);
  ios::sync_with_stdio(false);

  // input
  ll N, Q;
  cin >> N >> Q;

  // どこまでいけるか
  // VI H(N, N-1);
  // VI W(N, N-1);
  vector<S> A(N);
  ll init_val = N - 1; // 初期値
  rep(i, N) { A[i] = S{init_val, 1}; }
  lazy_segtree<S, op, e, F, mapping, composition, id> H(A);
  lazy_segtree<S, op, e, F, mapping, composition, id> W(A);

  // 左上領域
  ll h = N - 1;
  ll w = N - 1;

  ll white = 2 * N - 1;
  ll black = (N - 2) * (N - 2);

  while (Q--) {

    ll type;
    cin >> type;
    ll p;
    cin >> p;
    p--; // position
    debug(type, p);
    if (type == 2) {
      // (y,1)に置く
      // horizontalにひっくり返す
      if (p > h) {
        // 範囲外
        // white += H[p];
        // black -= H[p]-1;
        white += H.prod(p, p + 1).a;
        black -= H.prod(p, p + 1).a - 1;
      } else {
        // 範囲内
        h = p;

        // rep(i,w+1) W[i]=p;
        W.apply(0, w + 1, F{0LL, p});

        white += w;
        black -= w - 1;
      }
    }
    // type==1
    else {
      // verticalにひっくり返す
      if (p > w) {
        // 範囲外
        // white += W[p];
        // black -= W[p]-1;
        white += W.prod(p, p + 1).a;
        black -= W.prod(p, p + 1).a - 1;
      } else {
        // 範囲内
        w = p;

        // rep(i,h+1) H[i]=p;
        H.apply(0, h + 1, F{0LL, p});

        white += h;
        black -= h - 1;
      }
    }

    // debug(W);
    // debug(H);
    // debug(h,w);
    // debug(white,black);
    // cerr<<endl;
  }
  p(black);

  return 0;
}


Error: TLE

Fixed submission:

#ifdef LOCAL
#define _GLIBCXX_DEBUG
#define __clock__
#else
#pragma GCC optimize("Ofast")
#endif
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ld = long double;
using VI = vector<ll>;
using VV = vector<VI>;
using VS = vector<string>;
using PII = pair<ll, ll>;

// tourist set
template <typename A, typename B> string to_string(pair<A, B> p);

template <typename A, typename B, typename C>
string to_string(tuple<A, B, C> p);

template <typename A, typename B, typename C, typename D>
string to_string(tuple<A, B, C, D> p);

string to_string(const string &s) { return '"' + s + '"'; }

string to_string(const char *s) { return to_string((string)s); }

string to_string(bool b) { return (b ? "true" : "false"); }

string to_string(vector<bool> v) {
  bool first = true;
  string res = "{";
  for (int i = 0; i < static_cast<int>(v.size()); i++) {
    if (!first) {
      res += ", ";
    }
    first = false;
    res += to_string(v[i]);
  }
  res += "}";
  return res;
}

template <size_t N> string to_string(bitset<N> v) {
  string res = "";
  for (size_t i = 0; i < N; i++) {
    res += static_cast<char>('0' + v[i]);
  }
  return res;
}

template <typename A> string to_string(A v) {
  bool first = true;
  string res = "{";
  for (const auto &x : v) {
    if (!first) {
      res += ", ";
    }
    first = false;
    res += to_string(x);
  }
  res += "}";
  return res;
}

template <typename A, typename B> string to_string(pair<A, B> p) {
  return "(" + to_string(p.first) + ", " + to_string(p.second) + ")";
}

template <typename A, typename B, typename C>
string to_string(tuple<A, B, C> p) {
  return "(" + to_string(get<0>(p)) + ", " + to_string(get<1>(p)) + ", " +
         to_string(get<2>(p)) + ")";
}

template <typename A, typename B, typename C, typename D>
string to_string(tuple<A, B, C, D> p) {
  return "(" + to_string(get<0>(p)) + ", " + to_string(get<1>(p)) + ", " +
         to_string(get<2>(p)) + ", " + to_string(get<3>(p)) + ")";
}

void debug_out() { cerr << '\\n'; }

template <typename Head, typename... Tail> void debug_out(Head H, Tail... T) {
  cerr << " " << to_string(H);
  debug_out(T...);
}

#ifdef LOCAL
#define debug(...) cerr << "[" << #__VA_ARGS__ << "]:", debug_out(__VA_ARGS__)
#else
#define debug(...) 42
#endif
// tourist set end

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

#define FOR(i, a, b) for (ll i = (a); i < (b); ++i)
#define rep(i, b) FOR(i, 0, b)
#define ALL(v) (v).begin(), (v).end()
#define p(s) cout << (s) << '\\n'
#define p2(s, t) cout << (s) << " " << (t) << '\\n'
#define br() p("")
#define pn(s) cout << (#s) << " " << (s) << '\\n'
#define SZ(x) ((int)(x).size())
#define SORT(A) sort(ALL(A))
#define RSORT(A) sort(ALL(A), greater<ll>())
#define MP make_pair
#define p_yes() p("YES")
#define p_no() p("NO")
#define possible() p("Possible")
#define impossible() p("Impossible")

ll SUM(VI &V) { return accumulate(ALL(V), 0LL); }

ll MIN(VI &V) { return *min_element(ALL(V)); }
ll MAX(VI &V) { return *max_element(ALL(V)); }

void print_vector(VI &V) {
  ll n = V.size();
  rep(i, n) {
    if (i)
      cout << ' ';
    cout << V[i];
  }
  cout << endl;
}

ll gcd(ll a, ll b) {
  if (b == 0)
    return a;
  return gcd(b, a % b);
}

ll lcm(ll a, ll b) {
  ll g = gcd(a, b);
  return a / g * b;
}

// long double
using ld = long double;
#define EPS (1e-14)
#define equals(a, b) (fabs((a) - (b)) < EPS)

void no() {
  p_no();
  exit(0);
}
void yes() {
  p_yes();
  exit(0);
}

const ll mod = 1e9 + 7;
const ll inf = 1e18;
const double PI = acos(-1);

// snuke's mint
// auto mod int
// https://youtu.be/L8grWxBlIZ4?t=9858
// https://youtu.be/ERZuLAxZffQ?t=4807 : optimize
// https://youtu.be/8uowVvQ_-Mo?t=1329 : division
// const int mod = 1000000007;
struct mint {
  ll x; // typedef long long ll;
  mint(ll x = 0) : x((x % mod + mod) % mod) {}
  mint operator-() const { return mint(-x); }
  mint &operator+=(const mint a) {
    if ((x += a.x) >= mod)
      x -= mod;
    return *this;
  }
  mint &operator-=(const mint a) {
    if ((x += mod - a.x) >= mod)
      x -= mod;
    return *this;
  }
  mint &operator*=(const mint a) {
    (x *= a.x) %= mod;
    return *this;
  }
  mint operator+(const mint a) const {
    mint res(*this);
    return res += a;
  }
  mint operator-(const mint a) const {
    mint res(*this);
    return res -= a;
  }
  mint operator*(const mint a) const {
    mint res(*this);
    return res *= a;
  }
  mint pow(ll t) const {
    if (!t)
      return 1;
    mint a = pow(t >> 1);
    a *= a;
    if (t & 1)
      a *= *this;
    return a;
  }

  // for prime mod
  mint inv() const { return pow(mod - 2); }
  mint &operator/=(const mint a) { return (*this) *= a.inv(); }
  mint operator/(const mint a) const {
    mint res(*this);
    return res /= a;
  }
};

// #include <atcoder/dsu>
// using namespace atcoder; // 忘れがち

// for codeforces
void solve() {
  ll N;
  cin >> N;
  VI A(N);
  rep(i, N) { cin >> A[i]; }
}

int main() {
  cin.tie(0);
  ios::sync_with_stdio(false);

  // input
  ll N, Q;
  cin >> N >> Q;

  // どこまでいけるか
  VI H(N, N - 1);
  VI W(N, N - 1);

  // 左上領域
  ll h = N - 1;
  ll w = N - 1;

  ll white = 2 * N - 1;
  ll black = (N - 2) * (N - 2);

  while (Q--) {

    ll type;
    cin >> type;
    ll p;
    cin >> p;
    p--; // position
    debug(type, p);
    if (type == 2) {
      // (y,1)に置く
      // horizontalにひっくり返す
      if (p > h) {
        // 範囲外
        white += H[p];
        black -= H[p] - 1;
      } else {
        // 範囲内
        h = p;
        rep(i, w + 1) W[i] = p;
        white += w;
        black -= w - 1;
      }
    }
    // type==1
    else {
      // verticalにひっくり返す
      if (p > w) {
        // 範囲外
        white += W[p];
        black -= W[p] - 1;
      } else {
        // 範囲内
        w = p;
        rep(i, h + 1) H[i] = p;
        white += h;
        black -= h - 1;
      }
    }

    // debug(W);
    // debug(H);
    // debug(h,w);
    // debug(white,black);
    // cerr<<endl;
  }
  p(black);

  return 0;
}