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#include <bits/stdc++.h>
#define rep(i, a, b) for (int i = a; i <= b; i++)
#define per(i, a, b) for (int i = b; a <= i; i--)
#define cat(x) cerr << #x << " = " << x << '\n';
using ll = long long;
using ld = long double;
using namespace std;

const int N = 1 << 18;
const ld eps = 1e-12;

struct Tree {
	ll t[2 * N];

	void add(int x, ll y, int u = 1, int l = 0, int r = N - 1) {
		if (l == r) {
			t[u] = y;
			return;
		}
		int m = (l + r) / 2;
		if (x <= m)
			add(x, y, 2 * u, l, m);
		else
			add(x, y, 2 * u + 1, m + 1, r);
		t[u] = max(t[2 * u], t[2 * u + 1]);
	}

	int query(int x, ll need, int u = 1, int l = 0, int r = N - 1) {
		if (r < x || t[u] < need)
			return 0;
		if (l == r)
			return l;
		int m = (l + r) / 2;
		int L = query(x, need, 2 * u, l, m);
		if (L) return L;
		return query(x, need, 2 * u + 1, m + 1, r);
	}
} Tr;

int n, pointer[N];
string s1, s2, s3;
ld T, P, v0, v1, v2, v3;
vector<ld> w1, w3;

/* 1....2 -> ....12 */
ld f(ld p1, ld v1, ld p2, ld v2) {
	return (p2 - p1 - 1) / (v1 - v2);
}

int main() {
	cin.tie(0)->sync_with_stdio(0);

	cin >> n >> v0 >> v1 >> v2 >> v3;
	cin >> s1 >> s2 >> s3;

	rep(i, 0, n - 1)
		if (s1[i] == '#') {
			assert(i > 0);
			w1.push_back(i);
			if (s1[i - 1] == '#')
				pointer[i] = pointer[i - 1];
			else
				pointer[i] = i;
		}

	w3.push_back(1e15);
	per(i, 1, n - 1) 
		if (s3[i] == '#') {
			Tr.add(i, w3.back() - i - 1);
			w3.push_back(i);
		}
	reverse(w3.begin(), w3.end());

	int a = 0;
	while (a < n) {
		int l = a;
		while (l < n && s2[l] == '.') 
			l++;
		if (l == n)
			break;

		int r = l;
		while (r < n && s2[r] == '#')
			r++;
		r--;

		ld x = f(P, v0, l + v2 * T, v2);
		T += x;
		P += x * v0;
		
		ld opt_time = f(r + v2 * T, v2, P, v0);

		auto up = [&]() {
			auto it = lower_bound(w1.begin(), w1.end(), P - 1 + eps - v1 * T);
			if (it == w1.end())
				return opt_time;

			int id = pointer[int(*it)];
			return max(opt_time, f(r + v2 * T, v2, id - 1 + v1 * T, v1));
		};

		auto down = [&]() {
			auto it = lower_bound(w3.begin(), w3.end(), P - 1 + eps - v3 * T);
			if (it == w3.end())
				return opt_time;

			ld min_distance = opt_time * (v0 - v3) + 1;
			if ((*it + T * v3) - P >= min_distance - eps) {
				return opt_time;
			}

			int id = Tr.query(int(*it), ceil(min_distance - eps));
			return f(id + T * v3, v3, P, v2) + opt_time;
		};

		ld opt = min(up(), down());
		T += opt;
		P = r + T * v2 + 1;
		a = r + 1;
	}

	rep(i, 1, n - 1) {
		if (s1[i] == '#') {
			ld p1 = i + T * v1;
			if (p1 >= P - 1 - eps) {
				ld x = f(p1, v1, P, v0);
				T += x;
				P += v0 * x;
			}
		}
		if (s3[i] == '#') {
			ld p3 = i + T * v3;
			if (p3 >= P - 1 - eps) {
				ld x = f(p3, v3, P, v0);
				T += x;
				P += v0 * x;
			}
		}
	}

	cout << fixed << setprecision(15) << T << '\n';
	return 0;
}