Problem p03161 (C++)

Buggy submission (status: Runtime Error):
#include "bits/stdc++.h"
#pragma GCC optimize("Ofast")

// Begin Header {{{
using namespace std;

#ifndef DEBUG
#define dump(...)
#endif

#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define rep(i, n) for (intmax_t i = 0, i##_limit = (n); i < i##_limit; ++i)
#define reps(i, b, e)                                                          \
  for (intmax_t i = (b), i##_limit = (e); i <= i##_limit; ++i)
#define repr(i, b, e)                                                          \
  for (intmax_t i = (b), i##_limit = (e); i >= i##_limit; --i)
#define var(Type, ...)                                                         \
  Type __VA_ARGS__;                                                            \
  input(__VA_ARGS__)

constexpr size_t operator""_zu(unsigned long long value) { return value; };
constexpr intmax_t operator""_jd(unsigned long long value) { return value; };
constexpr uintmax_t operator""_ju(unsigned long long value) { return value; };

constexpr int INF = 0x3f3f3f3f;
constexpr intmax_t LINF = 0x3f3f3f3f3f3f3f3f_jd;

namespace moke {

template <class T> using MaxHeap = priority_queue<T, vector<T>, less<T>>;
template <class T> using MinHeap = priority_queue<T, vector<T>, greater<T>>;

inline void input() {}
template <class Head, class... Tail>
inline void input(Head &&head, Tail &&...tail) {
  cin >> head;
  input(forward<Tail>(tail)...);
}

template <class T> inline void input(vector<T> &vec) {
  for (auto &e : vec) {
    cin >> e;
  }
}

template <class T> inline void input(vector<vector<T>> &mat) {
  for (auto &vec : mat) {
    input(vec);
  }
}

inline void print() { cout << "\n"; }
template <class Head, class... Tail>
inline void print(Head &&head, Tail &&...tail) {
  static constexpr const char *delim[] = {"", " "};
  cout << head << delim[sizeof...(tail)];
  print(forward<Tail>(tail)...);
}

template <class T>
inline ostream &operator<<(ostream &strm, const vector<T> &vec) {
  static constexpr const char *delim[] = {" ", ""};
  for (const auto &e : vec) {
    strm << e << delim[&e == &vec.back()];
  }
  return strm;
}

template <class T> inline vector<T> make_v(const T &initValue, size_t sz) {
  return vector<T>(sz, initValue);
}

template <class T, class... Args>
inline auto make_v(const T &initValue, size_t sz, Args... args) {
  return vector<decltype(make_v<T>(initValue, args...))>(
      sz, make_v<T>(initValue, args...));
}

template <class A, class B> inline bool chmax(A &a, const B &b) noexcept {
  return b > a && (a = b, true);
}

template <class A, class B> inline bool chmin(A &a, const B &b) noexcept {
  return b < a && (a = b, true);
}

template <class A, class B>
inline common_type_t<A, B> min(const A &a, const B &b) noexcept {
  return a < b ? a : b;
}

template <class A, class B, class... Args>
inline common_type_t<A, B, Args...> min(const A &a, const B &b,
                                        const Args &...args) noexcept {
  return moke::min(a < b ? a : b, args...);
}

template <class A, class B>
inline common_type_t<A, B> max(const A &a, const B &b) noexcept {
  return a > b ? a : b;
}

template <class A, class B, class... Args>
inline common_type_t<A, B, Args...> max(const A &a, const B &b,
                                        const Args &...args) noexcept {
  return moke::max(a > b ? a : b, args...);
}

template <class A, class B>
inline common_type_t<A, B> diff(const A &a, const B &b) noexcept {
  return a < b ? b - a : a - b;
}

} // namespace moke

// }}} End Header

namespace moke {

size_t N, K;
vector<intmax_t> h;

vector<intmax_t> dp;

intmax_t rec(size_t idx) {
  if (idx == 0)
    return 0;

  auto &ret = dp[idx];
  if (~ret)
    return ret;

  ret = LINF;
  reps(i, 1, K) {
    if (idx - i >= 0) {
      chmin(ret, rec(idx - i) + diff(h[idx], h[idx - i]));
    }
  }

  return ret;
}

int main_() {
  ios_base::sync_with_stdio(false);
  cin.tie(nullptr);

  input(N, K);

  h.resize(N);
  input(h);

  dp.resize(N, -1);

  print(rec(N - 1));

  return 0;
}

} // namespace moke

signed main() { // {{{
  moke::main_();
  return 0;
} // }}}


Fixed submission:
#include "bits/stdc++.h"
#pragma GCC optimize("Ofast")

// Begin Header {{{
using namespace std;

#ifndef DEBUG
#define dump(...)
#endif

#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define rep(i, n) for (intmax_t i = 0, i##_limit = (n); i < i##_limit; ++i)
#define reps(i, b, e)                                                          \
  for (intmax_t i = (b), i##_limit = (e); i <= i##_limit; ++i)
#define repr(i, b, e)                                                          \
  for (intmax_t i = (b), i##_limit = (e); i >= i##_limit; --i)
#define var(Type, ...)                                                         \
  Type __VA_ARGS__;                                                            \
  input(__VA_ARGS__)

constexpr size_t operator""_zu(unsigned long long value) { return value; };
constexpr intmax_t operator""_jd(unsigned long long value) { return value; };
constexpr uintmax_t operator""_ju(unsigned long long value) { return value; };

constexpr int INF = 0x3f3f3f3f;
constexpr intmax_t LINF = 0x3f3f3f3f3f3f3f3f_jd;

namespace moke {

template <class T> using MaxHeap = priority_queue<T, vector<T>, less<T>>;
template <class T> using MinHeap = priority_queue<T, vector<T>, greater<T>>;

inline void input() {}
template <class Head, class... Tail>
inline void input(Head &&head, Tail &&...tail) {
  cin >> head;
  input(forward<Tail>(tail)...);
}

template <class T> inline void input(vector<T> &vec) {
  for (auto &e : vec) {
    cin >> e;
  }
}

template <class T> inline void input(vector<vector<T>> &mat) {
  for (auto &vec : mat) {
    input(vec);
  }
}

inline void print() { cout << "\n"; }
template <class Head, class... Tail>
inline void print(Head &&head, Tail &&...tail) {
  static constexpr const char *delim[] = {"", " "};
  cout << head << delim[sizeof...(tail)];
  print(forward<Tail>(tail)...);
}

template <class T>
inline ostream &operator<<(ostream &strm, const vector<T> &vec) {
  static constexpr const char *delim[] = {" ", ""};
  for (const auto &e : vec) {
    strm << e << delim[&e == &vec.back()];
  }
  return strm;
}

template <class T> inline vector<T> make_v(const T &initValue, size_t sz) {
  return vector<T>(sz, initValue);
}

template <class T, class... Args>
inline auto make_v(const T &initValue, size_t sz, Args... args) {
  return vector<decltype(make_v<T>(initValue, args...))>(
      sz, make_v<T>(initValue, args...));
}

template <class A, class B> inline bool chmax(A &a, const B &b) noexcept {
  return b > a && (a = b, true);
}

template <class A, class B> inline bool chmin(A &a, const B &b) noexcept {
  return b < a && (a = b, true);
}

template <class A, class B>
inline common_type_t<A, B> min(const A &a, const B &b) noexcept {
  return a < b ? a : b;
}

template <class A, class B, class... Args>
inline common_type_t<A, B, Args...> min(const A &a, const B &b,
                                        const Args &...args) noexcept {
  return moke::min(a < b ? a : b, args...);
}

template <class A, class B>
inline common_type_t<A, B> max(const A &a, const B &b) noexcept {
  return a > b ? a : b;
}

template <class A, class B, class... Args>
inline common_type_t<A, B, Args...> max(const A &a, const B &b,
                                        const Args &...args) noexcept {
  return moke::max(a > b ? a : b, args...);
}

template <class A, class B>
inline common_type_t<A, B> diff(const A &a, const B &b) noexcept {
  return a < b ? b - a : a - b;
}

} // namespace moke

// }}} End Header

namespace moke {

size_t N, K;
vector<intmax_t> h;

vector<intmax_t> dp;

intmax_t rec(int idx) {
  if (idx == 0)
    return 0;

  auto &ret = dp[idx];
  if (~ret)
    return ret;

  ret = LINF;
  reps(i, 1, K) {
    if (idx - i >= 0) {
      chmin(ret, rec(idx - i) + diff(h[idx], h[idx - i]));
    }
  }

  return ret;
}

int main_() {
  ios_base::sync_with_stdio(false);
  cin.tie(nullptr);

  input(N, K);

  h.resize(N);
  input(h);

  dp.resize(N, -1);

  print(rec(N - 1));

  return 0;
}

} // namespace moke

signed main() { // {{{
  moke::main_();
  return 0;
} // }}}