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#include <bits/stdc++.h>
#define REP(i,n) for (int _n=(n), i=0;i<_n;++i)
#define FOR(i,a,b) for (int i=(a),_b=(b);i<=_b;++i)
#define FORD(i,a,b) for (int i=(a),_b=(b);i>=_b;--i)
#define TRACE(x) std::cerr << "TRACE(" #x ")" << std::endl;
#define DEBUG(x) std::cerr << #x << " = " << (x) << std::endl;

void init_io() {
  std::cin.tie(nullptr);
  std::ios::sync_with_stdio(false);
}

struct Train {
  int begin = -1;
  int end = -1;
};

std::vector<Train> left_trains;
std::vector<Train> middle_trains;
std::vector<Train> right_trains;

// in meters / second
int full_speed;
int left_speed;
int right_speed;

std::int64_t fixed_point_denominator;

class FixedPoint {
public:
  explicit FixedPoint(int x = 0) : FixedPoint(x * fixed_point_denominator, FromQuanta{}) {}

  friend inline FixedPoint operator+(FixedPoint a, FixedPoint b) {
    return FixedPoint(a.val + b.val, FromQuanta{});
  }

  void operator+=(FixedPoint b) {
    val += b.val;
  }

  friend inline FixedPoint operator-(FixedPoint a, FixedPoint b) {
    return FixedPoint(a.val - b.val, FromQuanta{});
  }

  friend inline FixedPoint operator*(int a, FixedPoint b) {
    return FixedPoint(a * b.val, FromQuanta{});
  }

  FixedPoint divide_exact(int x) const {
    assert(val % x == 0);
    return FixedPoint(val / x, FromQuanta{});
  }

  static FixedPoint inverse(int x) {
    return FixedPoint(1).divide_exact(x);
  }

  friend inline bool operator<(FixedPoint a, FixedPoint b) {
    return a.val < b.val;
  }

  friend inline bool operator>(FixedPoint a, FixedPoint b) {
    return a.val > b.val;
  }

  friend inline bool operator<=(FixedPoint a, FixedPoint b) {
    return a.val <= b.val;
  }

  friend inline bool operator>=(FixedPoint a, FixedPoint b) {
    return a.val >= b.val;
  }

  double to_double() const {
    return static_cast<double>(val) / fixed_point_denominator;
  }

private:
  class FromQuanta {};
  explicit FixedPoint(std::int64_t v, FromQuanta): val(v) {}

  std::int64_t val;
};

FixedPoint inverse_full_speed;
FixedPoint inverse_left_speed;
FixedPoint inverse_right_speed;

std::vector<Train> read_trains(const int len) {
  std::vector<Train> trains;
  trains.reserve(len/2);
  {
    char first_char;
    std::cin >> first_char;
  }

  Train train;
  REP(i, len) {
    bool occupied = false;
    if (i < len-1) {
      char c;
      std::cin >> c;
      occupied = c == '#';
    }
    if (occupied) {
      if (train.begin == -1) {
        train.begin = i;
      }
    } else {
      if (train.begin != -1) {
        train.end = i + 1;
        trains.push_back(train);
        train = Train{};
      }
    }
  }
  return trains;
}

void read_input() {
  int len;
  int middle_speed;
  std::cin >> len >> full_speed >> left_speed >> middle_speed >> right_speed;

  full_speed -= middle_speed;
  left_speed -= middle_speed;
  right_speed = middle_speed - right_speed;
  assert(0 < left_speed && left_speed < full_speed && full_speed <= 140);
  assert(0 < right_speed && right_speed <= 140);

  // at most 140^5 < 54e9
  fixed_point_denominator = static_cast<std::int64_t>(right_speed) * left_speed * full_speed *
    (full_speed - left_speed) * (full_speed + right_speed);
  // makes range of FixedPoint go up to 170 million

  inverse_full_speed = FixedPoint::inverse(full_speed);
  inverse_left_speed = FixedPoint::inverse(left_speed);
  inverse_right_speed = FixedPoint::inverse(right_speed);

  left_trains = read_trains(len);
  middle_trains = read_trains(len);
  right_trains = read_trains(len);
}

FixedPoint solve() {
  FixedPoint current_time{0};
  int pos = 0;

  auto next_left_train = left_trains.begin();
  auto next_right_train = right_trains.begin();
  int prev_right_train_end = 0;

  for (const Train &middle_train : middle_trains) {
    // Catch up to the back of the middle train.
    current_time += (middle_train.begin - pos) * inverse_full_speed;
    pos = middle_train.begin;

    // Overtaking duration assuming we can go at full speed.
    const FixedPoint overtake_duration = (middle_train.end - pos) * inverse_full_speed;

    // Skip left trains that we have already passed -- we never have to hit them again.
    while (next_left_train != left_trains.end() &&
           (pos - next_left_train->end) * inverse_left_speed >= current_time) {
      ++next_left_train;
    }

    // Assume we can go left at full speed.
    FixedPoint overtake_time = current_time + overtake_duration;

    // Check if we get stuck behind a left train.
    if (next_left_train != left_trains.end()) {
      const FixedPoint overtake_behind_left =
        (middle_train.end - next_left_train->begin) * inverse_left_speed;
      overtake_time = std::max(overtake_time, overtake_behind_left);
    }

    // overtake_time is now the best we can do on the left.
    // See if we can go right faster.
    for (;;) {
      FixedPoint shift_right_time = (prev_right_train_end - pos) * inverse_right_speed;
      shift_right_time = std::max(current_time, shift_right_time);

      const FixedPoint overtake_right_time = shift_right_time + overtake_duration;

      // Not fast enough.
      if (overtake_right_time >= overtake_time) break;

      // Are we hitting the next right train?
      if (next_right_train != right_trains.end() &&
          (next_right_train->begin - middle_train.end) * inverse_right_speed < overtake_right_time) {
        // We would hit the next train on the right.
        // Going left is even slower, so we can never use space before the right train: skip that space
        // and repeat.
        prev_right_train_end = next_right_train->end;
        ++next_right_train;
      } else {
        // Not hitting: go right!
        overtake_time = overtake_right_time;
        break;
      }
    }

    current_time = overtake_time;
    pos = middle_train.end;
  }

  // We have passed all middle trains, pedal to the metal!
  FixedPoint finish_time = current_time;

  if (!left_trains.empty()) {
    // current_time <= 200000 (since we can just follow the last left train)
    // left_speed * current_time <= 28M
    // still fits in FixedPoint which goes up to 170M
    const FixedPoint pass_all_left =
      current_time +
      (FixedPoint(left_trains.back().end - pos) + left_speed * current_time)
        .divide_exact(full_speed - left_speed);

    finish_time = std::max(finish_time, pass_all_left);
  }

  if (!right_trains.empty()) {
    const FixedPoint pass_all_right =
      current_time +
      (FixedPoint(right_trains.back().end - pos) - right_speed * current_time)
        .divide_exact(full_speed + right_speed);

    finish_time = std::max(finish_time, pass_all_right);
  }

  return finish_time;
}

int main() {
  init_io();
  read_input();
  const FixedPoint res = solve();
  std::cout << std::fixed << std::setprecision(15) << res.to_double() << "\n";
}