Problem p02695 (C++)

Buggy submission (status: Runtime Error):
#include <bits/stdc++.h>
using namespace std;

#define INF_LL (int64)1e18
#define INF (int32)1e9
#define REP(i, n) for (int64 i = 0; i < (n); i++)
#define FOR(i, a, b) for (int64 i = (a); i < (b); i++)
#define all(x) x.begin(), x.end()
#define fs first
#define sc second

using int32 = int_fast32_t;
using uint32 = uint_fast32_t;
using int64 = int_fast64_t;
using uint64 = uint_fast64_t;
using PII = pair<int32, int32>;
using PLL = pair<int64, int64>;

const double eps = 1e-10;

template <typename A, typename B> inline void chmin(A &a, B b) {
  if (a > b)
    a = b;
}
template <typename A, typename B> inline void chmax(A &a, B b) {
  if (a < b)
    a = b;
}

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...));
}

template <typename T, typename U, typename... V>
typename enable_if<is_same<T, U>::value != 0>::type fill_v(U &u, const V... v) {
  u = U(v...);
}

template <typename T, typename U, typename... V>
typename enable_if<is_same<T, U>::value == 0>::type fill_v(U &u, const V... v) {
  for (auto &e : u)
    fill_v<T>(e, v...);
}

int64 N;
vector<int64> a;
vector<int64> G[212345];
vector<int64> res;
stack<PLL> undo;
vector<int64> lis;

void dfs(int64 v, int64 p) {
  int64 idx = lower_bound(all(lis), a[v]) - lis.begin();
  undo.emplace(idx, lis[idx]);
  lis[idx] = a[v];
  res[v] = lower_bound(all(lis), INF_LL) - lis.begin();

  for (auto &u : G[v]) {
    if (u == p)
      continue;
    dfs(u, v);
  }

  lis[undo.top().fs] = undo.top().sc;
  undo.pop();
}

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

  int64 N, M, Q;
  cin >> N >> M >> Q;
  vector<int> comb(M + N - 1, 0);
  REP(i, N) comb[M - i - 1] = 1;
  vector<int64> a(Q), b(Q), c(Q), d(Q);
  REP(i, Q) { cin >> a[i] >> b[i] >> c[i] >> d[i]; }
  int64 res = 0;
  do {
    vector<int64> A;
    int64 cnt = 0;
    REP(i, comb.size()) {
      if (comb[i])
        A.push_back(cnt + 1);
      else
        cnt++;
    }
    int64 sum = 0;
    REP(i, Q) {
      if (A[b[i] - 1] - A[a[i] - 1] == c[i])
        sum += d[i];
    }
    chmax(res, sum);
  } while (next_permutation(all(comb)));
  cout << res << endl;
}


Fixed submission:
#include <bits/stdc++.h>
using namespace std;

#define INF_LL (int64)1e18
#define INF (int32)1e9
#define REP(i, n) for (int64 i = 0; i < (n); i++)
#define FOR(i, a, b) for (int64 i = (a); i < (b); i++)
#define all(x) x.begin(), x.end()
#define fs first
#define sc second

using int32 = int_fast32_t;
using uint32 = uint_fast32_t;
using int64 = int_fast64_t;
using uint64 = uint_fast64_t;
using PII = pair<int32, int32>;
using PLL = pair<int64, int64>;

const double eps = 1e-10;

template <typename A, typename B> inline void chmin(A &a, B b) {
  if (a > b)
    a = b;
}
template <typename A, typename B> inline void chmax(A &a, B b) {
  if (a < b)
    a = b;
}

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...));
}

template <typename T, typename U, typename... V>
typename enable_if<is_same<T, U>::value != 0>::type fill_v(U &u, const V... v) {
  u = U(v...);
}

template <typename T, typename U, typename... V>
typename enable_if<is_same<T, U>::value == 0>::type fill_v(U &u, const V... v) {
  for (auto &e : u)
    fill_v<T>(e, v...);
}

int64 N;
vector<int64> a;
vector<int64> G[212345];
vector<int64> res;
stack<PLL> undo;
vector<int64> lis;

void dfs(int64 v, int64 p) {
  int64 idx = lower_bound(all(lis), a[v]) - lis.begin();
  undo.emplace(idx, lis[idx]);
  lis[idx] = a[v];
  res[v] = lower_bound(all(lis), INF_LL) - lis.begin();

  for (auto &u : G[v]) {
    if (u == p)
      continue;
    dfs(u, v);
  }

  lis[undo.top().fs] = undo.top().sc;
  undo.pop();
}

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

  int64 N, M, Q;
  cin >> N >> M >> Q;
  vector<int> comb(M + N - 1, 0);
  REP(i, N) comb[M + N - 1 - i - 1] = 1;
  vector<int64> a(Q), b(Q), c(Q), d(Q);
  REP(i, Q) { cin >> a[i] >> b[i] >> c[i] >> d[i]; }
  int64 res = 0;
  do {
    vector<int64> A;
    int64 cnt = 0;
    REP(i, comb.size()) {
      if (comb[i])
        A.push_back(cnt + 1);
      else
        cnt++;
    }
    int64 sum = 0;
    REP(i, Q) {
      if (A[b[i] - 1] - A[a[i] - 1] == c[i])
        sum += d[i];
    }
    chmax(res, sum);
  } while (next_permutation(all(comb)));
  cout << res << endl;
}