Problem p02551 (C++) — buggy submission, verdict: Runtime Error

#include <algorithm>
#include <climits>
#include <cmath>
#include <iomanip>
#include <iostream>
#include <map>
#include <queue>
#include <stack>
#include <vector>

using namespace std;

using Pair = pair<int, int>;
using lint = long long;
using ll = long long;
#define rep(i, n) for (int i = 0; i < (n); i++)

// const int mod = 1e9 + 7;
// const int mod = 998244353;

template <typename T> vector<T> make_v(size_t a) { return vector<T>(a); }

template <typename T, typename... Ts> auto make_v(size_t a, Ts... ts) {
  return vector<decltype(make_v<T>(ts...))>(a, make_v<T>(ts...));
}
// Segment Tree Beats
// - l<=i<r について、 A_i の値を min(A_i, x) に更新
// - l<=i<r について、 A_i の値を max(A_i, x) に更新
// - l<=i<r の中の A_i の最大値を求める
// - l<=i<r の中の A_i の最小値を求める
// - l<=i<r の A_i の和を求める
// - l<=i<r について、 A_i の値に x を加える
// - l<=i<r について、 A_i の値を x に更新

#define N 10003

class SegmentTree {
  static const ll inf = 1e18;
  struct Node {
    Node *left, *right;
    ll max_v, smax_v, max_c;
    ll min_v, smin_v, min_c;
    ll sum;
    ll len, ladd, lval;

    Node() : left(0), right(0), ladd(0), lval(inf) {}

    void init(ll x) {
      max_v = min_v = sum = x;
      smax_v = -inf;
      smin_v = inf;
      max_c = min_c = 1;
    }

    void init_empty() {
      max_v = smax_v = -inf;
      min_v = smin_v = inf;
      max_c = min_c = 0;
    }

    void update_max(ll x) {
      sum += (x - max_v) * max_c;

      if (max_v == min_v) {
        max_v = min_v = x;
      } else if (max_v == smin_v) {
        max_v = smin_v = x;
      } else {
        max_v = x;
      }

      if (lval != inf && x < lval) {
        lval = x;
      }
    }

    void update_min(ll x) {
      sum += (x - min_v) * min_c;

      if (max_v == min_v) {
        max_v = min_v = x;
      } else if (max_v == smin_v) {
        min_v = smax_v = x;
      } else {
        min_v = x;
      }

      if (lval != inf && lval < x) {
        lval = x;
      }
    }

    void addall(ll x) {
      max_v += x;
      if (smax_v != -inf)
        smax_v += x;
      min_v += x;
      if (smin_v != inf)
        smin_v += x;

      sum += len * x;
      if (lval != inf) {
        lval += x;
      } else {
        ladd += x;
      }
    }

    void updateall(ll x) {
      max_v = min_v = x;
      smax_v = -inf;
      smin_v = inf;
      max_c = min_c = len;

      sum = len * x;
      lval = x;
      ladd = 0;
    }

    void push() {
      if (lval != inf) {
        left->updateall(lval);
        right->updateall(lval);
        lval = inf;
        return;
      }

      if (ladd != 0) {
        left->addall(ladd);
        right->addall(ladd);
        ladd = 0;
      }

      if (max_v < left->max_v) {
        left->update_max(max_v);
      }
      if (left->min_v < min_v) {
        left->update_min(min_v);
      }

      if (max_v < right->max_v) {
        right->update_max(max_v);
      }
      if (right->min_v < min_v) {
        right->update_min(min_v);
      }
    }

    void update() {
      sum = left->sum + right->sum;

      if (left->max_v < right->max_v) {
        max_v = right->max_v;
        max_c = right->max_c;
        smax_v = max(left->max_v, right->smax_v);
      } else if (left->max_v > right->max_v) {
        max_v = left->max_v;
        max_c = left->max_c;
        smax_v = max(left->smax_v, right->max_v);
      } else {
        max_v = left->max_v;
        max_c = left->max_c + right->max_c;
        smax_v = max(left->smax_v, right->smax_v);
      }

      if (left->min_v < right->min_v) {
        min_v = left->min_v;
        min_c = left->min_c;
        smin_v = min(left->smin_v, right->min_v);
      } else if (left->min_v > right->min_v) {
        min_v = right->min_v;
        min_c = right->min_c;
        smin_v = min(left->min_v, right->smin_v);
      } else {
        min_v = left->min_v;
        min_c = left->min_c + right->min_c;
        smin_v = min(left->smin_v, right->smin_v);
      }
    }
  };

  int n, n0;
  Node *root;

  void _update_min(ll x, int a, int b, Node *nd, int l, int r) {
    if (b <= l || r <= a || nd->max_v <= x) {
      return;
    }
    if (a <= l && r <= b && nd->smax_v < x) {
      nd->update_max(x);
      return;
    }

    nd->push();
    _update_min(x, a, b, nd->left, l, (l + r) / 2);
    _update_min(x, a, b, nd->right, (l + r) / 2, r);
    nd->update();
  }

  void _update_max(ll x, int a, int b, Node *nd, int l, int r) {
    if (b <= l || r <= a || x <= nd->min_v) {
      return;
    }
    if (a <= l && r <= b && x < nd->smin_v) {
      nd->update_min(x);
      return;
    }

    nd->push();
    _update_max(x, a, b, nd->left, l, (l + r) / 2);
    _update_max(x, a, b, nd->right, (l + r) / 2, r);
    nd->update();
  }

  void _add_val(ll x, int a, int b, Node *nd, int l, int r) {
    if (b <= l || r <= a) {
      return;
    }
    if (a <= l && r <= b) {
      nd->addall(x);
      return;
    }

    nd->push();
    _add_val(x, a, b, nd->left, l, (l + r) / 2);
    _add_val(x, a, b, nd->right, (l + r) / 2, r);
    nd->update();
  }

  void _update_val(ll x, int a, int b, Node *nd, int l, int r) {
    if (b <= l || r <= a) {
      return;
    }
    if (a <= l && r <= b) {
      nd->updateall(x);
      return;
    }

    nd->push();
    _update_val(x, a, b, nd->left, l, (l + r) / 2);
    _update_val(x, a, b, nd->right, (l + r) / 2, r);
    nd->update();
  }

  ll _query_max(int a, int b, Node *nd, int l, int r) {
    if (b <= l || r <= a) {
      return -inf;
    }
    if (a <= l && r <= b) {
      return nd->max_v;
    }
    nd->push();
    ll lv = _query_max(a, b, nd->left, l, (l + r) / 2);
    ll rv = _query_max(a, b, nd->right, (l + r) / 2, r);
    return max(lv, rv);
  }

  ll _query_min(int a, int b, Node *nd, int l, int r) {
    if (b <= l || r <= a) {
      return inf;
    }
    if (a <= l && r <= b) {
      return nd->min_v;
    }
    nd->push();
    ll lv = _query_min(a, b, nd->left, l, (l + r) / 2);
    ll rv = _query_min(a, b, nd->right, (l + r) / 2, r);
    return min(lv, rv);
  }

  ll _query_sum(int a, int b, Node *nd, int l, int r) {
    if (b <= l || r <= a) {
      return 0;
    }
    if (a <= l && r <= b) {
      return nd->sum;
    }
    nd->push();
    ll lv = _query_sum(a, b, nd->left, l, (l + r) / 2);
    ll rv = _query_sum(a, b, nd->right, (l + r) / 2, r);
    return lv + rv;
  }

public:
  SegmentTree(int n, ll *a) : n(n) {
    n0 = 1;
    while (n0 < n)
      n0 <<= 1;

    Node *nds = new Node[2 * n0];
    root = nds;

    nds[0].len = n0;
    for (int i = 0; i < n0 - 1; ++i) {
      nds[i].left = &nds[2 * i + 1];
      nds[i].right = &nds[2 * i + 2];
      nds[2 * i + 1].len = nds[2 * i + 2].len = (nds[i].len >> 1);
    }

    for (int i = 0; i < n; ++i)
      nds[n0 - 1 + i].init(a[i]);
    for (int i = n; i < n0; ++i)
      nds[n0 - 1 + i].init_empty();
    for (int i = n0 - 2; i >= 0; i--)
      nds[i].update();
  }

  void update_min(int a, int b, ll x) { _update_min(x, a, b, root, 0, n0); }

  void update_max(int a, int b, ll x) { _update_max(x, a, b, root, 0, n0); }

  void add_val(int a, int b, ll x) { _add_val(x, a, b, root, 0, n0); }

  void update_val(int a, int b, ll x) { _update_val(x, a, b, root, 0, n0); }

  ll query_max(int a, int b) { return _query_max(a, b, root, 0, n0); }

  ll query_min(int a, int b) { return _query_min(a, b, root, 0, n0); }

  ll query_sum(int a, int b) { return _query_sum(a, b, root, 0, n0); }
};

int main() {
  lint n, q;
  cin >> n >> q;
  lint al[n];
  rep(i, n) { al[i] = n - 1; }
  SegmentTree t1(n, al), t2(n, al);
  t1.update_val(0, n, n - 1);
  t2.update_val(0, n, n - 1);
  lint cnt = (n - 2) * (n - 2);
  rep(i, q) {
    int a, b;
    cin >> a >> b;
    b--;
    if (a == 1) {
      cnt -= t1.query_max(b, b + 1) - 1;
      t2.update_min(0, t1.query_max(b, b + 1) + 1, b);
    }
    if (a == 2) {
      cnt -= t2.query_max(b, b + 1) - 1;
      t1.update_min(0, t2.query_max(b, b + 1) + 1, b);
    }
  }
  cout << cnt << endl;
}


Error: -11

Fixed submission:

#include <algorithm>
#include <climits>
#include <cmath>
#include <iomanip>
#include <iostream>
#include <map>
#include <queue>
#include <stack>
#include <vector>

using namespace std;

using Pair = pair<int, int>;
using lint = long long;

#define rep(i, n) for (int i = 0; i < (n); i++)

// const int mod = 1e9 + 7;
// const int mod = 998244353;

template <typename T> vector<T> make_v(size_t a) { return vector<T>(a); }

template <typename T, typename... Ts> auto make_v(size_t a, Ts... ts) {
  return vector<decltype(make_v<T>(ts...))>(a, make_v<T>(ts...));
}
#include <algorithm>
using namespace std;
using ll = long long;

// Segment Tree Beats
// - l<=i<r について、 A_i の値を min(A_i, x) に更新
// - l<=i<r について、 A_i の値を max(A_i, x) に更新
// - l<=i<r の中の A_i の最大値を求める
// - l<=i<r の中の A_i の最小値を求める
// - l<=i<r の A_i の和を求める
// - l<=i<r について、 A_i の値に x を加える
// - l<=i<r について、 A_i の値を x に更新

#define N 10003

class SegmentTree {
  const ll inf = 1e18;
  int n, n0;
  ll max_v[4 * N], smax_v[4 * N], max_c[4 * N];
  ll min_v[4 * N], smin_v[4 * N], min_c[4 * N];
  ll sum[4 * N];
  ll len[4 * N], ladd[4 * N], lval[4 * N];

  void update_node_max(int k, ll x) {
    sum[k] += (x - max_v[k]) * max_c[k];

    if (max_v[k] == min_v[k]) {
      max_v[k] = min_v[k] = x;
    } else if (max_v[k] == smin_v[k]) {
      max_v[k] = smin_v[k] = x;
    } else {
      max_v[k] = x;
    }

    if (lval[k] != inf && x < lval[k]) {
      lval[k] = x;
    }
  }
  void update_node_min(int k, ll x) {
    sum[k] += (x - min_v[k]) * min_c[k];

    if (max_v[k] == min_v[k]) {
      max_v[k] = min_v[k] = x;
    } else if (smax_v[k] == min_v[k]) {
      min_v[k] = smax_v[k] = x;
    } else {
      min_v[k] = x;
    }

    if (lval[k] != inf && lval[k] < x) {
      lval[k] = x;
    }
  }

  void push(int k) {
    if (n0 - 1 <= k)
      return;

    if (lval[k] != inf) {
      updateall(2 * k + 1, lval[k]);
      updateall(2 * k + 2, lval[k]);
      lval[k] = inf;
      return;
    }

    if (ladd[k] != 0) {
      addall(2 * k + 1, ladd[k]);
      addall(2 * k + 2, ladd[k]);
      ladd[k] = 0;
    }

    if (max_v[k] < max_v[2 * k + 1]) {
      update_node_max(2 * k + 1, max_v[k]);
    }
    if (min_v[2 * k + 1] < min_v[k]) {
      update_node_min(2 * k + 1, min_v[k]);
    }

    if (max_v[k] < max_v[2 * k + 2]) {
      update_node_max(2 * k + 2, max_v[k]);
    }
    if (min_v[2 * k + 2] < min_v[k]) {
      update_node_min(2 * k + 2, min_v[k]);
    }
  }

  void update(int k) {
    sum[k] = sum[2 * k + 1] + sum[2 * k + 2];

    if (max_v[2 * k + 1] < max_v[2 * k + 2]) {
      max_v[k] = max_v[2 * k + 2];
      max_c[k] = max_c[2 * k + 2];
      smax_v[k] = max(max_v[2 * k + 1], smax_v[2 * k + 2]);
    } else if (max_v[2 * k + 1] > max_v[2 * k + 2]) {
      max_v[k] = max_v[2 * k + 1];
      max_c[k] = max_c[2 * k + 1];
      smax_v[k] = max(smax_v[2 * k + 1], max_v[2 * k + 2]);
    } else {
      max_v[k] = max_v[2 * k + 1];
      max_c[k] = max_c[2 * k + 1] + max_c[2 * k + 2];
      smax_v[k] = max(smax_v[2 * k + 1], smax_v[2 * k + 2]);
    }

    if (min_v[2 * k + 1] < min_v[2 * k + 2]) {
      min_v[k] = min_v[2 * k + 1];
      min_c[k] = min_c[2 * k + 1];
      smin_v[k] = min(smin_v[2 * k + 1], min_v[2 * k + 2]);
    } else if (min_v[2 * k + 1] > min_v[2 * k + 2]) {
      min_v[k] = min_v[2 * k + 2];
      min_c[k] = min_c[2 * k + 2];
      smin_v[k] = min(min_v[2 * k + 1], smin_v[2 * k + 2]);
    } else {
      min_v[k] = min_v[2 * k + 1];
      min_c[k] = min_c[2 * k + 1] + min_c[2 * k + 2];
      smin_v[k] = min(smin_v[2 * k + 1], smin_v[2 * k + 2]);
    }
  }

  void _update_min(ll x, int a, int b, int k, int l, int r) {
    if (b <= l || r <= a || max_v[k] <= x) {
      return;
    }
    if (a <= l && r <= b && smax_v[k] < x) {
      update_node_max(k, x);
      return;
    }

    push(k);
    _update_min(x, a, b, 2 * k + 1, l, (l + r) / 2);
    _update_min(x, a, b, 2 * k + 2, (l + r) / 2, r);
    update(k);
  }

  void _update_max(ll x, int a, int b, int k, int l, int r) {
    if (b <= l || r <= a || x <= min_v[k]) {
      return;
    }
    if (a <= l && r <= b && x < smin_v[k]) {
      update_node_min(k, x);
      return;
    }

    push(k);
    _update_max(x, a, b, 2 * k + 1, l, (l + r) / 2);
    _update_max(x, a, b, 2 * k + 2, (l + r) / 2, r);
    update(k);
  }

  void addall(int k, ll x) {
    max_v[k] += x;
    if (smax_v[k] != -inf)
      smax_v[k] += x;
    min_v[k] += x;
    if (smin_v[k] != inf)
      smin_v[k] += x;

    sum[k] += len[k] * x;
    if (lval[k] != inf) {
      lval[k] += x;
    } else {
      ladd[k] += x;
    }
  }

  void updateall(int k, ll x) {
    max_v[k] = x;
    smax_v[k] = -inf;
    min_v[k] = x;
    smin_v[k] = inf;
    max_c[k] = min_c[k] = len[k];

    sum[k] = x * len[k];
    lval[k] = x;
    ladd[k] = 0;
  }

  void _add_val(ll x, int a, int b, int k, int l, int r) {
    if (b <= l || r <= a) {
      return;
    }
    if (a <= l && r <= b) {
      addall(k, x);
      return;
    }

    push(k);
    _add_val(x, a, b, 2 * k + 1, l, (l + r) / 2);
    _add_val(x, a, b, 2 * k + 2, (l + r) / 2, r);
    update(k);
  }

  void _update_val(ll x, int a, int b, int k, int l, int r) {
    if (b <= l || r <= a) {
      return;
    }
    if (a <= l && r <= b) {
      updateall(k, x);
      return;
    }

    push(k);
    _update_val(x, a, b, 2 * k + 1, l, (l + r) / 2);
    _update_val(x, a, b, 2 * k + 2, (l + r) / 2, r);
    update(k);
  }

  ll _query_max(int a, int b, int k, int l, int r) {
    if (b <= l || r <= a) {
      return -inf;
    }
    if (a <= l && r <= b) {
      return max_v[k];
    }
    push(k);
    ll lv = _query_max(a, b, 2 * k + 1, l, (l + r) / 2);
    ll rv = _query_max(a, b, 2 * k + 2, (l + r) / 2, r);
    return max(lv, rv);
  }

  ll _query_min(int a, int b, int k, int l, int r) {
    if (b <= l || r <= a) {
      return inf;
    }
    if (a <= l && r <= b) {
      return min_v[k];
    }
    push(k);
    ll lv = _query_min(a, b, 2 * k + 1, l, (l + r) / 2);
    ll rv = _query_min(a, b, 2 * k + 2, (l + r) / 2, r);
    return min(lv, rv);
  }

  ll _query_sum(int a, int b, int k, int l, int r) {
    if (b <= l || r <= a) {
      return 0;
    }
    if (a <= l && r <= b) {
      return sum[k];
    }
    push(k);
    ll lv = _query_sum(a, b, 2 * k + 1, l, (l + r) / 2);
    ll rv = _query_sum(a, b, 2 * k + 2, (l + r) / 2, r);
    return lv + rv;
  }

public:
  SegmentTree(int n) { SegmentTree(n, nullptr); }

  SegmentTree(int n, ll *a) : n(n) {
    n0 = 1;
    while (n0 < n)
      n0 <<= 1;

    for (int i = 0; i < 2 * n0; ++i)
      ladd[i] = 0, lval[i] = inf;
    len[0] = n0;
    for (int i = 0; i < n0 - 1; ++i)
      len[2 * i + 1] = len[2 * i + 2] = (len[i] >> 1);

    for (int i = 0; i < n; ++i) {
      max_v[n0 - 1 + i] = min_v[n0 - 1 + i] = sum[n0 - 1 + i] =
          (a != nullptr ? a[i] : 0);
      smax_v[n0 - 1 + i] = -inf;
      smin_v[n0 - 1 + i] = inf;
      max_c[n0 - 1 + i] = min_c[n0 - 1 + i] = 1;
    }

    for (int i = n; i < n0; ++i) {
      max_v[n0 - 1 + i] = smax_v[n0 - 1 + i] = -inf;
      min_v[n0 - 1 + i] = smin_v[n0 - 1 + i] = inf;
      max_c[n0 - 1 + i] = min_c[n0 - 1 + i] = 0;
    }
    for (int i = n0 - 2; i >= 0; i--) {
      update(i);
    }
  }

  // range minimize query
  void update_min(int a, int b, ll x) { _update_min(x, a, b, 0, 0, n0); }

  // range maximize query
  void update_max(int a, int b, ll x) { _update_max(x, a, b, 0, 0, n0); }

  // range add query
  void add_val(int a, int b, ll x) { _add_val(x, a, b, 0, 0, n0); }

  // range update query
  void update_val(int a, int b, ll x) { _update_val(x, a, b, 0, 0, n0); }

  // range minimum query
  ll query_max(int a, int b) { return _query_max(a, b, 0, 0, n0); }

  // range maximum query
  ll query_min(int a, int b) { return _query_min(a, b, 0, 0, n0); }

  // range sum query
  ll query_sum(int a, int b) { return _query_sum(a, b, 0, 0, n0); }
};
int main() {
  lint n, q;
  cin >> n >> q;
  SegmentTree t1(n), t2(n);
  t1.update_val(0, n, n - 1);
  t2.update_val(0, n, n - 1);
  lint cnt = (n - 2) * (n - 2);
  rep(i, n) {
    int a, b;
    cin >> a >> b;
    b--;
    if (a == 1) {
      cnt -= t1.query_max(b, b + 1) - 1;
      t2.update_min(0, t1.query_max(b, b + 1) + 1, b);
    }
    if (a == 2) {
      cnt -= t2.query_max(b, b + 1) - 1;
      t1.update_min(0, t2.query_max(b, b + 1) + 1, b);
    }
  }
  cout << cnt << endl;
}