Language: C++

#include <bits/stdc++.h>
using namespace std;
#define BIT(n) (1LL << (n))
#define BITF(n, i) (((n) >> (i)) & 1)
#define REP(i, n) for (int i = 0; i < n; i++)
#define FOR(i, m, n) for (int i = m; i < n; i++)
#define REPI(i, x) for (int i = 1; i <= x; i++)
#define FORI(i, m, n) for (int i = m; i <= n; i++)
#define REPR(i, n) for (int i = n; i >= 0; i--)
#define REPZ(i, x) for (int i = 0; i <= x; i++)
#define FORA(i, n) for (auto &&i : n)
#define POW(a, b) ((int)(pow(a, b) + .5))
#define MODULO(a, b) (((a) % (b)) < 0 ? (a) % (b) + (b) : (a) % (b))
#define DUMPOUT cerr
// vector
template <typename T> istream &operator>>(istream &is, vector<T> &vec) {
  for (T &x : vec) is >> x;
  return is;
}
// pair
template <typename T, typename U> ostream &operator<<(ostream &os, pair<T, U> &pair_var) {
  os << "(" << pair_var.first << ", " << pair_var.second << ")";
  return os;
}
// vector
template <typename T> ostream &operator<<(ostream &os, const vector<T> &vec) {
  os << "{";
  REP(i, (int)vec.size())
  os << vec[i] << (i + 1 == (int)vec.size() ? "" : ", ");
  os << "}";
  return os;
}
// map
template <typename T, typename U> ostream &operator<<(ostream &os, map<T, U> &map_var) {
  os << "{";
  FORA(itr, map_var) {
    os << *itr;
    itr++;
    if (itr != map_var.end()) os << ", ";
    itr--;
  }
  os << "}";
  return os;
}
// set
template <typename T> ostream &operator<<(ostream &os, set<T> &set_var) {
  os << "{";
  FORA(itr, set_var) {
    os << *itr;
    itr++;
    if (itr != set_var.end()) os << ", ";
    itr--;
  }
  os << "}";
  return os;
}
void dump_func() { DUMPOUT << endl; }
template <class Head, class... Tail> void dump_func(Head &&head, Tail &&... tail) {
  DUMPOUT << head;
  if (sizeof...(Tail) > 0) DUMPOUT << ", ";
  dump_func(std::move(tail)...);
}
#ifdef DEBUG_
#define DEB
#define DUMP(...)                                                             \
  DUMPOUT << "  " << string(#__VA_ARGS__) << ": "                             \
          << "[" << to_string(__LINE__) << ":" << __FUNCTION__ << "]" << endl \
          << "    ",                                                          \
      dump_func(__VA_ARGS__)
#define PRINTARR(x, y)                                     \
  cerr << #x << "=\n";                                     \
  for (auto itr = x; itr != y; itr++) cerr << *itr << " "; \
  cerr << endl;
#define PRINTARR2(x, i0, i1)                                       \
  cerr << #x << "=\n";                                             \
  for (int ii0 = 0; ii0 < i0; ii0++) {                             \
    for (int ii1 = 0; ii1 < i1; ii1++) cerr << x[ii0][ii1] << " "; \
    cerr << endl;                                                  \
  }
#else
#define DEB if (false)
#define DUMP(...)
#define PRINTARR(x, y)
#define PRINTARR2(x, i0, i1)
#endif
#define ALL(v) v.begin(), v.end()
#define fst first
#define snd second
#define mp make_pair
#define pb push_back
#define epb emplace_back
#define int long long
#define pint pair<int, int>
#define pdouble pair<double, double>
#define ld long double
using namespace std;
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 (a > b) {
    a = b;
    return 1;
  }
  return 0;
}
template <class T> using vec = std::vector<T>;
template <class T> void print(const T &x) { cout << x << "\n"; }
const int MOD = 1000000007, INF0 = 1061109567, INF = INF0 * INF0;
const double EPS = 1e-7, PI = acos(-1.0);
const int dx[4] = {1, 0, -1, 0}, dy[4] = {0, 1, 0, -1};
/*  set UnionFind BIT deque queue multiset segtree priority_queue bitset map vector
[&] { return; }();下のスラッシュを2つ追加しただけ.上のスラッシュを2つにすれば外れる.
//*/
#define MAXN 2100
vec<string> s(3);

bool hantei[3][(2 * MAXN + 1)];  // a-b b-c c-a
bool ok(string a, string b, int pos) {
  if (pos < 0) {
    swap(a, b);
    pos *= -1;
  }
  if (pos >= (int)a.size()) {
    return true;
  } else {
    int last = min((int)a.size(), (int)b.size() + pos);
    DUMP(pos, a.size(), b.size(), last - pos);

    //    assert()
    string a0 = a.substr(pos, last - pos);
    string b0 = b.substr(0, last - pos);
    bool ok = true;
    REP(i, last - pos) {
      char u = a0[i];
      char v = b0[i];
      bool ret = false;
      if (u == '?' || v == '?')
        ret = true;
      else if (u == v)
        ret = true;
      if (!ret) {
        ok = false;
        break;
      }
    }
    //    if (pos <= 3) DUMP(a0, b0, ok);
    return ok;
  }
}
signed main() {
  cin.tie(0), ios::sync_with_stdio(false);
  cout << fixed << setprecision(12);
  REP(i, 3) cin >> s[i];
  sort(ALL(s));
  //  REP(i, 3) sA[i] = s[i];

  REP(j, 3) {
    for (int i = -MAXN; i <= MAXN; i++) {
      hantei[j][i + MAXN] = ok(s[j], s[(j + 1) % 3], i);
    }
  }
  //  PRINTARR2(hantei, 3, 2 * MAXN + 1);
  int ans = INF;
  int tmpA[6][3] = {{0, 1, 2}, {0, 2, 1}, {1, 0, 2}, {1, 2, 0}, {2, 0, 1}, {2, 1, 0}};
  bool flg[6][3] = {{true, true, true}, {false, false, false}, {false, false, false}, {true, true, true}, {true, true, true}, {false, false, false}};
  REP(index, 6) {
    int tmp0 = tmpA[index][0];
    int tmp1 = tmpA[index][1];
    int tmp2 = tmpA[index][2];

    DUMP(s[0], s[1], s[2], index);
    assert(tmp0 + tmp1 + tmp2 == 3);
    for (int i = 0; i <= (int)s[tmp0].size(); i++) {
      int ret0 = flg[index][0] ? MAXN + i : MAXN - i;
      if (hantei[tmp2][ret0]) {
        for (int j = 0; j <= (int)s[tmp1].size(); j++) {
          int ret1 = flg[index][1] ? MAXN + j : MAXN - j;
          int ret2 = flg[index][2] ? MAXN + (i + j) : MAXN - (i + j);
          if (ret2 < 0) ret2 = 0;
          if (ret2 >= 2 * MAXN) ret2 = 2 * MAXN;
          if (hantei[tmp0][ret1] && hantei[tmp1][ret2]) {
            int val = max({(int)s[tmp0].size(), i + (int)s[tmp1].size(), i + j + (int)s[tmp2].size()});
            DUMP(val, ok);
            chmin(ans, val);
            break;
          }
          //            break;
        }
      }
      break;
    }
  }
}
assert(ans <= s[0].size() + s[1].size() + s[2].size());
print(ans);  // ans重複
}

Compiler output:
In file included from /usr/include/c++/14/cassert:44,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:106,
                 from a.cc:1:
a.cc:199:1: error: expected unqualified-id before 'static_cast'
  199 | assert(ans <= s[0].size() + s[1].size() + s[2].size());
      | ^~~~~~
a.cc:199:1: error: expected ')' before 'static_cast'
  199 | assert(ans <= s[0].size() + s[1].size() + s[2].size());
      | ^~~~~~
a.cc:200:6: error: expected constructor, destructor, or type conversion before '(' token
  200 | print(ans);  // ans重複
      |      ^
a.cc:201:1: error: expected declaration before '}' token
  201 | }
      | ^