Problem p02704 (C++) — buggy submission, verdict: Runtime Error

#include <bits/stdc++.h> // clang-format off
using Int = long long;
#define REP_(i, a_, b_, a, b, ...) for (Int i = (a), lim##i = (b); i < lim##i; i++)
#define REP(i, ...) REP_(i, __VA_ARGS__, __VA_ARGS__, 0, __VA_ARGS__)
struct SetupIO { SetupIO() { std::cin.tie(nullptr), std::ios::sync_with_stdio(false), std::cout << std::fixed << std::setprecision(13); } } setup_io;
#ifndef dump
#define dump(...)
#endif // clang-format on

/**
 *    author:  knshnb
 *    created: Sun May  3 13:27:58 JST 2020
 **/

template <class T, class S> T make_vec(S x) { return x; }
template <class T, class... Ts> auto make_vec(size_t n, Ts... ts) {
  return std::vector<decltype(make_vec<T>(ts...))>(n, make_vec<T>(ts...));
}

void no() {
  std::cout << -1 << std::endl;
  exit(0);
}

using ull = unsigned long long;
const Int K = 64;
signed main() {
  Int n;
  std::cin >> n;
  std::vector<Int> S(n), T(n);
  std::vector<ull> U(n), V(n);
  REP(i, n) std::cin >> S[i];
  REP(i, n) std::cin >> T[i];
  REP(i, n) std::cin >> U[i];
  REP(i, n) std::cin >> V[i];
  auto solve_1bit = [&n](const std::vector<Int> &x, const std::vector<Int> &y) {
    auto ret = make_vec<Int>(n, n, -1);
    auto row = make_vec<Int>(n, 2, true);
    auto col = make_vec<Int>(n, 2, true);
    REP(i, n) {
      if (x[i] < 2)
        row[i][x[i]] = false;
    }
    REP(j, n) {
      if (y[j] < 2)
        col[j][y[j]] = false;
    }
    REP(i, n) {
      REP(j, n) {
        if (x[i] >= 2)
          ret[i][j] = x[i] - 2;
        if (y[j] >= 2)
          ret[i][j] = y[j] - 2;
        if (x[i] == y[j] && x[i] < 2)
          ret[i][j] = x[i];

        if (ret[i][j] != -1)
          row[i][ret[i][j]] = col[j][ret[i][j]] = true;
      }
    }
    Int cnti = std::count_if(x.begin(), x.end(), [](Int a) { return a < 2; });
    Int cntj = std::count_if(y.begin(), y.end(), [](Int a) { return a < 2; });
    if (cnti <= 1 || cntj <= 1) {
      REP(i, n) {
        REP(j, n) {
          if (ret[i][j] != -1)
            continue;
          if (row[i][0] && col[j][0]) {
            ret[i][j] = 1;
          } else {
            ret[i][j] = 0;
          }
          row[i][ret[i][j]] = col[j][ret[i][j]] = true;
        }
      }
      // REP(i, n) REP(j, 2) if (!row[i][j]) assert(0);
      // REP(i, n) REP(j, 2) if (!col[i][j]) assert(0);
    } else {
      Int ci = 0;
      REP(i, n) {
        if (x[i] >= 2)
          continue;
        Int cj = 0;
        REP(j, n) {
          if (y[j] >= 2)
            continue;
          ret[i][j] = (ci + cj) % 2;
          cj++;
        }
        ci++;
      }
    }
    return ret;
  };
  auto ans = make_vec<ull>(n, n, 0);
  REP(k, K) {
    std::vector<Int> x(n), y(n);
    auto trans = [](Int p, Int q) {
      if (p == 0 && q == 0)
        return 0;
      if (p == 1 && q == 1)
        return 1;
      if (p == 1 && q == 0)
        return 2;
      if (p == 0 && q == 1)
        return 3;
      assert(0);
    };
    REP(i, n) x[i] = trans(S[i], U[i] >> k & 1);
    REP(j, n) y[j] = trans(T[j], V[j] >> k & 1);
    auto tmp = solve_1bit(x, y);
    REP(i, n) {
      REP(j, n) { ans[i][j] |= ull(tmp[i][j]) << k; }
    }
  }

  // verify
  ull all = 0;
  REP(i, K) all |= 1ull << i;
  REP(i, n) {
    ull acc = S[i] ? 0 : all;
    REP(j, n) {
      if (S[i]) {
        acc |= ans[i][j];
      } else {
        acc &= ans[i][j];
      }
    }
    if (acc != U[i])
      no();
  }
  REP(j, n) {
    ull acc = T[j] ? 0 : all;
    REP(i, n) {
      if (T[j]) {
        acc |= ans[i][j];
      } else {
        acc &= ans[i][j];
      }
    }
    if (acc != V[j])
      no();
  }
  REP(i, n) {
    REP(j, n) std::cout << ans[i][j] << " ";
    std::cout << "\\n";
  }
}


Error: WA

Fixed submission:

#include <bits/stdc++.h> // clang-format off
using Int = long long;
#define REP_(i, a_, b_, a, b, ...) for (Int i = (a), lim##i = (b); i < lim##i; i++)
#define REP(i, ...) REP_(i, __VA_ARGS__, __VA_ARGS__, 0, __VA_ARGS__)
struct SetupIO { SetupIO() { std::cin.tie(nullptr), std::ios::sync_with_stdio(false), std::cout << std::fixed << std::setprecision(13); } } setup_io;
#ifndef dump
#define dump(...)
#endif // clang-format on

/**
 *    author:  knshnb
 *    created: Sun May  3 13:27:58 JST 2020
 **/

template <class T, class S> T make_vec(S x) { return x; }
template <class T, class... Ts> auto make_vec(size_t n, Ts... ts) {
  return std::vector<decltype(make_vec<T>(ts...))>(n, make_vec<T>(ts...));
}

void no() {
  std::cout << -1 << std::endl;
  exit(0);
}

using ull = unsigned long long;
const Int K = 64;
signed main() {
  Int n;
  std::cin >> n;
  std::vector<Int> S(n), T(n);
  std::vector<ull> U(n), V(n);
  REP(i, n) std::cin >> S[i];
  REP(i, n) std::cin >> T[i];
  REP(i, n) std::cin >> U[i];
  REP(i, n) std::cin >> V[i];
  auto solve_1bit = [&n](const std::vector<Int> &x, const std::vector<Int> &y) {
    auto ret = make_vec<Int>(n, n, -1);
    auto row = make_vec<Int>(n, 2, true);
    auto col = make_vec<Int>(n, 2, true);
    REP(i, n) {
      if (x[i] < 2)
        row[i][x[i]] = false;
    }
    REP(j, n) {
      if (y[j] < 2)
        col[j][y[j]] = false;
    }
    REP(i, n) {
      REP(j, n) {
        if (x[i] >= 2)
          ret[i][j] = x[i] - 2;
        if (y[j] >= 2)
          ret[i][j] = y[j] - 2;
        if (x[i] == y[j] && x[i] < 2)
          ret[i][j] = x[i];

        if (ret[i][j] != -1)
          row[i][ret[i][j]] = col[j][ret[i][j]] = true;
      }
    }
    Int cnti = std::count_if(x.begin(), x.end(), [](Int a) { return a < 2; });
    Int cntj = std::count_if(y.begin(), y.end(), [](Int a) { return a < 2; });
    if (cnti <= 1 || cntj <= 1) {
      REP(i, n) {
        REP(j, n) {
          if (ret[i][j] != -1)
            continue;
          if (row[i][0] && col[j][0]) {
            ret[i][j] = 1;
          } else {
            ret[i][j] = 0;
          }
          row[i][ret[i][j]] = col[j][ret[i][j]] = true;
        }
      }
      REP(i, n) REP(j, 2) if (!row[i][j]) assert(0);
      REP(i, n) REP(j, 2) if (!col[i][j]) assert(0);
    } else {
      Int ci = 0;
      REP(i, n) {
        if (x[i] >= 2)
          continue;
        Int cj = 0;
        REP(j, n) {
          if (y[j] >= 2)
            continue;
          ret[i][j] = (ci + cj) % 2;
          cj++;
        }
        ci++;
      }
    }
    return ret;
  };
  auto ans = make_vec<ull>(n, n, 0);
  REP(k, K) {
    std::vector<Int> x(n), y(n);
    auto trans = [](Int p, Int q) {
      if (p == 0 && q == 0)
        return 0;
      if (p == 1 && q == 1)
        return 1;
      if (p == 1 && q == 0)
        return 2;
      if (p == 0 && q == 1)
        return 3;
      assert(0);
    };
    REP(i, n) x[i] = trans(S[i], U[i] >> k & 1);
    REP(j, n) y[j] = trans(T[j], V[j] >> k & 1);
    auto tmp = solve_1bit(x, y);
    REP(i, n) {
      REP(j, n) { ans[i][j] |= ull(tmp[i][j]) << k; }
    }
  }

  // verify
  ull all = 0;
  REP(i, K) all |= 1ull << i;
  REP(i, n) {
    ull acc = S[i] ? 0 : all;
    REP(j, n) {
      if (S[i]) {
        acc |= ans[i][j];
      } else {
        acc &= ans[i][j];
      }
    }
    if (acc != U[i])
      no();
  }
  REP(j, n) {
    ull acc = T[j] ? 0 : all;
    REP(i, n) {
      if (T[j]) {
        acc |= ans[i][j];
      } else {
        acc &= ans[i][j];
      }
    }
    if (acc != V[j])
      no();
  }
  REP(i, n) {
    REP(j, n) std::cout << ans[i][j] << " ";
    std::cout << "\\n";
  }
}