Problem p02537 (C++) — buggy submission, verdict: Runtime Error

#include <algorithm>
#include <bitset>
#include <cmath>
#include <cstdio>
#include <deque>
#include <functional>
#include <iostream>
#include <map>
#include <queue>
#include <set>
#include <stack>
#include <string>
#include <utility>
#include <vector>
#define rep(i, n, m) for (int i = (n); i < (int)(m); i++)
#define reps(i, n, m) for (int i = (n); i <= (int)(m); i++)
#define all(v) v.begin(), v.end()
#define allr(v) v.rbegin(), v.rend()
#define SZ(x) ((int)(x).size())
#define pb push_back
#define fs first
#define sc second
#define lb lower_bound
#define ub upper_bound
#define LB(a, x) lb(all(a), x) - a.begin()
#define UB(a, x) ub(all(a), x) - a.begin()
#define printfdouble(x) printf("%.20f\\n", (x))
#define chartoint(c) (int)((c) - '0')
#define chartoll(c) (long long)((c) - '0')
#define MOD 1000000007
#define itn int
#define enld endl
#define ednl endl
#define icn cin
#define cotu cout
#define Endl endl
#define stirng string
using namespace std;
typedef long long ll;
const double pi = 3.141592653589793;
using Graph = vector<vector<int>>;
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;
}
template <typename A, size_t N, typename T>
void Fill(A (&array)[N], const T &val) {
  std::fill((T *)array, (T *)(array + N), val);
}

template <typename T> class SegTree {
  int n;
  vector<T> data;
  T def;
  function<T(T, T)> operation;
  function<T(T, T)> update;

  T _query(int a, int b, int k, int l, int r) {
    if (r <= a || b <= l)
      return def;

    if (a <= l && r <= b)
      return data[k];
    else {
      T c1 = _query(a, b, 2 * k + 1, l, (l + r) / 2);
      T c2 = _query(a, b, 2 * k + 2, (l + r) / 2, r);
      return operation(c1, c2);
    }
  }

public:
  SegTree(int _n, T _def, function<T(T, T)> _operation,
          function<T(T, T)> _update)
      : def(_def), operation(_operation), update(_update) {
    n = 1;
    while (n < _n) {
      n *= 2;
    }
    data = vector<T>(2 * n - 1, def);
  }

  void change(int i, T x) {
    i += n - 1;
    data[i] = update(data[i], x);
    while (i > 0) {
      i = (i - 1) / 2;
      data[i] = operation(data[i * 2 + 1], data[i * 2 + 2]);
    }
  }

  T query(int a, int b) { return _query(a, b, 0, 0, n); }

  T operator[](int i) { return data[i + n - 1]; }

  T get(int i) { return data[i + n - 1]; }
};

int main() {
  cin.tie(0);
  ios::sync_with_stdio(false);
  int n, k;
  cin >> n >> k;
  SegTree<int> st(
      300100, 0, [](int a, int b) { return max(a, b); },
      [](int a, int b) { return b; });
  int a[300100];
  rep(i, 0, n) cin >> a[i];
  rep(i, 0, n) {
    int l = max(0, a[i] - k);
    int r = min(300100, a[i] + k + 1);
    int tmp = st.query(l, r);
    if (st.get(a[i]) < tmp + 1) {
      st.change(a[i], tmp + 1);
    }
  }

  int ans = st.query(0, 300100);
  cout << ans << endl;
  return 0;
}


Error: 0

Fixed submission:

#include <algorithm>
#include <bitset>
#include <cmath>
#include <cstdio>
#include <deque>
#include <functional>
#include <iostream>
#include <map>
#include <queue>
#include <set>
#include <stack>
#include <string>
#include <utility>
#include <vector>
#define rep(i, n, m) for (int i = (n); i < (int)(m); i++)
#define reps(i, n, m) for (int i = (n); i <= (int)(m); i++)
#define all(v) v.begin(), v.end()
#define allr(v) v.rbegin(), v.rend()
#define SZ(x) ((int)(x).size())
#define pb push_back
#define fs first
#define sc second
#define lb lower_bound
#define ub upper_bound
#define LB(a, x) lb(all(a), x) - a.begin()
#define UB(a, x) ub(all(a), x) - a.begin()
#define printfdouble(x) printf("%.20f\\n", (x))
#define chartoint(c) (int)((c) - '0')
#define chartoll(c) (long long)((c) - '0')
#define MOD 1000000007
#define itn int
#define enld endl
#define ednl endl
#define icn cin
#define cotu cout
#define Endl endl
#define stirng string
using namespace std;
typedef long long ll;
const double pi = 3.141592653589793;
using Graph = vector<vector<int>>;
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;
}
template <typename A, size_t N, typename T>
void Fill(A (&array)[N], const T &val) {
  std::fill((T *)array, (T *)(array + N), val);
}

template <typename T> class SegTree {
  int n;
  vector<T> data;
  T def;
  function<T(T, T)> operation;
  function<T(T, T)> update;

  T _query(int a, int b, int k, int l, int r) {
    if (r <= a || b <= l)
      return def;

    if (a <= l && r <= b)
      return data[k];
    else {
      T c1 = _query(a, b, 2 * k + 1, l, (l + r) / 2);
      T c2 = _query(a, b, 2 * k + 2, (l + r) / 2, r);
      return operation(c1, c2);
    }
  }

public:
  SegTree(int _n, T _def, function<T(T, T)> _operation,
          function<T(T, T)> _update)
      : def(_def), operation(_operation), update(_update) {
    n = 1;
    while (n < _n) {
      n *= 2;
    }
    data = vector<T>(2 * n - 1, def);
  }

  void change(int i, T x) {
    i += n - 1;
    data[i] = update(data[i], x);
    while (i > 0) {
      i = (i - 1) / 2;
      data[i] = operation(data[i * 2 + 1], data[i * 2 + 2]);
    }
  }

  T query(int a, int b) { return _query(a, b, 0, 0, n); }

  T operator[](int i) { return data[i + n - 1]; }

  T get(int i) { return data[i + n - 1]; }
};

int main() {
  cin.tie(0);
  ios::sync_with_stdio(false);
  int n, k;
  cin >> n >> k;
  SegTree<int> st(
      n + 1, 0, [](int a, int b) { return max(a, b); },
      [](int a, int b) { return b; });
  int a[300100];
  rep(i, 0, n) cin >> a[i];
  rep(i, 0, n) {
    int l = max(0, a[i] - k);
    int r = min(n, a[i] + k + 1);
    int tmp = st.query(l, r);
    if (st.get(a[i]) < tmp + 1) {
      st.change(a[i], tmp + 1);
    }
  }

  int ans = st.query(0, n);
  cout << ans << endl;
  return 0;
}