Problem p02745 (C++)

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

// @@ !! LIM(debug)
// --> f:<< debug
// ---- inserted function << from util.cc
template <typename T1, typename T2>
ostream &operator<<(ostream &os, const pair<T1, T2> &p) {
  os << "(" << p.first << ", " << p.second << ")";
  return os;
}

template <typename T1, typename T2, typename T3>
ostream &operator<<(ostream &os, const tuple<T1, T2, T3> &t) {
  os << "(" << get<0>(t) << ", " << get<1>(t) << ", " << get<2>(t) << ")";
  return os;
}

template <typename T1, typename T2, typename T3, typename T4>
ostream &operator<<(ostream &os, const tuple<T1, T2, T3, T4> &t) {
  os << "(" << get<0>(t) << ", " << get<1>(t) << ", " << get<2>(t) << ", "
     << get<3>(t) << ")";
  return os;
}

template <typename T> ostream &operator<<(ostream &os, const vector<T> &v) {
  os << '[';
  for (auto it = v.begin(); it != v.end(); it++) {
    if (it != v.begin())
      os << ", ";
    os << *it;
  }
  os << ']';

  return os;
}

template <typename T> ostream &operator<<(ostream &os, const set<T> &v) {
  os << '{';
  for (auto it = v.begin(); it != v.end(); it++) {
    if (it != v.begin())
      os << ", ";
    os << *it;
  }
  os << '}';

  return os;
}

template <typename T> ostream &operator<<(ostream &os, const multiset<T> &v) {
  os << '{';
  for (auto it = v.begin(); it != v.end(); it++) {
    if (it != v.begin())
      os << ", ";
    os << *it;
  }
  os << '}';

  return os;
}

template <typename T1, typename T2>
ostream &operator<<(ostream &os, const map<T1, T2> &mp) {
  os << '[';
  for (auto it = mp.begin(); it != mp.end(); it++) {
    if (it != mp.begin())
      os << ", ";
    os << it->first << ": " << it->second;
  }
  os << ']';

  return os;
}

template <typename T, typename T2, typename T3>
ostream &operator<<(ostream &os, const priority_queue<T, T2, T3> &orig) {
  priority_queue<T, T2, T3> pq(orig);
  bool first = true;
  os << '[';
  while (!pq.empty()) {
    T x = pq.top();
    pq.pop();
    if (!first)
      os << ", ";
    os << x;
    first = false;
  }
  return os << ']';
}
// ---- end <<
// ---- inserted library file debug.cc
template <class... Args> string dbgFormat(const char *fmt, Args... args) {
  size_t len = snprintf(nullptr, 0, fmt, args...);
  char buf[len + 1];
  snprintf(buf, len + 1, fmt, args...);
  return string(buf);
}

template <class Head> void dbgLog(Head &&head) { cerr << head << endl; }

template <class Head, class... Tail> void dbgLog(Head &&head, Tail &&...tail) {
  cerr << head << " ";
  dbgLog(forward<Tail>(tail)...);
}

#if DEBUG
#define DLOG(...) dbgLog(__VA_ARGS__)
#define DFMT(...) cerr << dbgFormat(__VA_ARGS__) << endl
#define DCALL(func, ...) func(__VA_ARGS__)
#else
#define DLOG(...)
#define DFMT(...)
#define DCALL(func, ...)
#endif

// ---- end debug.cc
// @@ !! LIM  -- end mark --

int main(int argc, char *argv[]) {
  ios_base::sync_with_stdio(false);
  cin.tie(nullptr);
  cout << setprecision(20);

  string a, b, c;
  cin >> a >> b >> c;
  ll na = a.size(), nb = b.size(), nc = c.size();
  ll shift = 2 * (na + nb + nc);
  vector<bool> vab(2 * shift, true), vbc(2 * shift, true), vac(2 * shift, true);
  auto fill = [&](auto &vec, string x, string y) -> void {
    for (ll i = 0; i < (ll)x.size(); i++) {
      for (ll j = 0; j < (ll)y.size(); j++) {
        if (!(x.at(i) == y.at(j) || x.at(i) == '?' || y.at(i) == '?')) {
          vec.at(shift + i - j) = false;
        }
      }
    }
  };
  fill(vab, a, b);
  fill(vac, a, c);
  fill(vbc, b, c);
  ll ans = LLONG_MAX;
  for (ll i = -(nb + nc); i <= na + max(nb, nc); i++) {
    if (!vab.at(shift + i))
      continue;
    for (ll j = -(nb + nc); j <= na + max(nb, nc); j++) {
      if (!vac.at(shift + j))
        continue;
      if (!vbc.at(shift + (j - i)))
        continue;
      ll len = max(na, max(i + nb, j + nc)) - min(0LL, min(i, j));
      DLOG("i", i, "j", j, "len", len);
      ans = min(ans, len);
    }
  }
  cout << ans << endl;

  return 0;
}


Fixed submission:
#include <bits/stdc++.h>
#include <cassert>
typedef long long int ll;
using namespace std;

// @@ !! LIM(debug)
// --> f:<< debug
// ---- inserted function << from util.cc
template <typename T1, typename T2>
ostream &operator<<(ostream &os, const pair<T1, T2> &p) {
  os << "(" << p.first << ", " << p.second << ")";
  return os;
}

template <typename T1, typename T2, typename T3>
ostream &operator<<(ostream &os, const tuple<T1, T2, T3> &t) {
  os << "(" << get<0>(t) << ", " << get<1>(t) << ", " << get<2>(t) << ")";
  return os;
}

template <typename T1, typename T2, typename T3, typename T4>
ostream &operator<<(ostream &os, const tuple<T1, T2, T3, T4> &t) {
  os << "(" << get<0>(t) << ", " << get<1>(t) << ", " << get<2>(t) << ", "
     << get<3>(t) << ")";
  return os;
}

template <typename T> ostream &operator<<(ostream &os, const vector<T> &v) {
  os << '[';
  for (auto it = v.begin(); it != v.end(); it++) {
    if (it != v.begin())
      os << ", ";
    os << *it;
  }
  os << ']';

  return os;
}

template <typename T> ostream &operator<<(ostream &os, const set<T> &v) {
  os << '{';
  for (auto it = v.begin(); it != v.end(); it++) {
    if (it != v.begin())
      os << ", ";
    os << *it;
  }
  os << '}';

  return os;
}

template <typename T> ostream &operator<<(ostream &os, const multiset<T> &v) {
  os << '{';
  for (auto it = v.begin(); it != v.end(); it++) {
    if (it != v.begin())
      os << ", ";
    os << *it;
  }
  os << '}';

  return os;
}

template <typename T1, typename T2>
ostream &operator<<(ostream &os, const map<T1, T2> &mp) {
  os << '[';
  for (auto it = mp.begin(); it != mp.end(); it++) {
    if (it != mp.begin())
      os << ", ";
    os << it->first << ": " << it->second;
  }
  os << ']';

  return os;
}

template <typename T, typename T2, typename T3>
ostream &operator<<(ostream &os, const priority_queue<T, T2, T3> &orig) {
  priority_queue<T, T2, T3> pq(orig);
  bool first = true;
  os << '[';
  while (!pq.empty()) {
    T x = pq.top();
    pq.pop();
    if (!first)
      os << ", ";
    os << x;
    first = false;
  }
  return os << ']';
}
// ---- end <<
// ---- inserted library file debug.cc
template <class... Args> string dbgFormat(const char *fmt, Args... args) {
  size_t len = snprintf(nullptr, 0, fmt, args...);
  char buf[len + 1];
  snprintf(buf, len + 1, fmt, args...);
  return string(buf);
}

template <class Head> void dbgLog(Head &&head) { cerr << head << endl; }

template <class Head, class... Tail> void dbgLog(Head &&head, Tail &&...tail) {
  cerr << head << " ";
  dbgLog(forward<Tail>(tail)...);
}

#if DEBUG
#define DLOG(...) dbgLog(__VA_ARGS__)
#define DFMT(...) cerr << dbgFormat(__VA_ARGS__) << endl
#define DCALL(func, ...) func(__VA_ARGS__)
#else
#define DLOG(...)
#define DFMT(...)
#define DCALL(func, ...)
#endif

// ---- end debug.cc
// @@ !! LIM  -- end mark --

int main(int argc, char *argv[]) {
  ios_base::sync_with_stdio(false);
  cin.tie(nullptr);
  cout << setprecision(20);

  string a, b, c;
  cin >> a >> b >> c;
  ll na = a.size(), nb = b.size(), nc = c.size();
  ll shift = 2 * (na + nb + nc);
  vector<bool> vab(2 * shift, true), vbc(2 * shift, true), vac(2 * shift, true);
  auto fill = [&](auto &vec, string x, string y) -> void {
    for (ll i = 0; i < (ll)x.size(); i++) {
      for (ll j = 0; j < (ll)y.size(); j++) {
        if (!(x.at(i) == y.at(j) || x.at(i) == '?' || y.at(j) == '?')) {
          vec.at(shift + i - j) = false;
        }
      }
    }
  };
  fill(vab, a, b);
  fill(vac, a, c);
  fill(vbc, b, c);
  ll ans = LLONG_MAX;
  for (ll i = -(nb + nc); i <= na + max(nb, nc); i++) {
    if (!vab.at(shift + i))
      continue;
    for (ll j = -(nb + nc); j <= na + max(nb, nc); j++) {
      if (!vac.at(shift + j))
        continue;
      if (!vbc.at(shift + (j - i)))
        continue;
      ll len = max(na, max(i + nb, j + nc)) - min(0LL, min(i, j));
      DLOG("i", i, "j", j, "len", len);
      ans = min(ans, len);
    }
  }
  cout << ans << endl;

  return 0;
}