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#include <bits/stdc++.h>
using namespace std;
#define REP(i,a,b) for (int i = (a); i <= (b); ++i)
#define REPD(i,a,b) for (int i = (a); i >= (b); --i)
#define FORI(i,n) REP(i,1,n)
#define FOR(i,n) REP(i,0,int(n)-1)
#define mp make_pair
#define pb push_back
#define pii pair<int,int>
#define ll long long
#define SZ(x) int((x).size())
#define DBG(v) cerr << #v << " = " << (v) << endl;
#define FOREACH(i,t) for (typeof(t.begin()) i=t.begin(); i!=t.end(); i++)
#define fi first
#define se second

struct TimeType {
	ll num, den;
	TimeType(int x=0) {
		num = x;
		den = 1;
	}
	TimeType(int x, int y) {
		num = x;
		den = y;
		if (den == 0) {
			num = 1e8;
			den = 1;
		}
	}
	inline void norm() {
		ll g = __gcd(num, den);
		num /= g;
		den /= g;
		if (den < 0) {
			num = -num;
			den = -den;
		}
	}
	TimeType operator+ (const TimeType &t) {
		TimeType res;
		ll newden = den / __gcd(den, t.den) * t.den;
		ll num1 = num * (newden / den), num2 = t.num * (newden / t.den);
		res.num = num1 + num2;
		res.den = newden;
		res.norm();
		return res;
	}
	TimeType operator- (const TimeType &t) {
		TimeType res;
		ll newden = den / __gcd(den, t.den) * t.den;
		ll num1 = num * (newden / den), num2 = t.num * (newden / t.den);
		res.num = num1 - num2;
		res.den = newden;
		res.norm();
		return res;
	}
	TimeType operator* (const int &ti) {
		TimeType t(ti);
		TimeType res;
		res.num = num * t.num;
		res.den = den * t.den;
		res.norm();
		return res;
	}
	TimeType operator* (const TimeType &t) {
		TimeType res;
		res.num = num * t.num;
		res.den = den * t.den;
		res.norm();
		return res;
	}
	TimeType operator/ (const TimeType &t) {
		TimeType res;
		res.num = num * t.den;
		res.den = den * t.num;
		res.norm();
		return res;
	}
	bool operator!= (const TimeType t) const {
		return num != t.num || den != t.den;
	}
	bool operator< (const TimeType t) const {
		return num*t.den < t.num*den;
	}
	bool operator<= (const TimeType t) const {
		return num*t.den <= t.num*den;
	}
	int floor() {
		return num / den;
	}
	double real() {
		return 1.0 * num / den;
	}
};
ostream& operator << (ostream &out, TimeType in) {
	//out << in.num << "/" << in.den;
	out << in.real() << " (" << in.num << "/" << in.den << ")";
	return out;
}

const int N = 200200;
const TimeType inf(1,0);

int L, v0, v[4];

char stmp[N];
int occ[4][N];
int dst[4][N];
int endlane[4];

TimeType ans_free;
TimeType besttime[4][N];

struct State {
	TimeType t;
	int lane, pos;
	State(TimeType t_=0.0, int lane_=-1, int pos_=0) {
		t=t_;
		lane=lane_;
		pos=pos_;
	}
	bool operator< (const State &s) const {
		if (t != s.t) return s.t < t;
		if (lane != s.lane) return lane < s.lane;
		return pos < s.pos;
	}
	bool bad() { return lane == -1; }
};

priority_queue<State> Q;
void add(State s) {
	if (besttime[s.lane][s.pos] <= s.t) {
		//cerr << "not adding lane " << s.lane << ", position " << s.pos << " at time " << s.t << " : there was time = " << besttime[s.lane][s.pos] << "available\n";
		return;
	}
	besttime[s.lane][s.pos] = s.t;
	Q.push(s);
	//cerr << "adding lane " << s.lane << ", position " << s.pos << " at time " << s.t << "\n";
}
void add_free_car(State s) {
	//cerr << "free car at lane " << s.lane << ", position " << s.pos << " at time " << s.t << "\n";
	TimeType ans = 0;
	FORI(i,3) if (i!=s.lane) {
		TimeType td = (TimeType(endlane[i] - s.pos) + s.t * (v[i]-v[s.lane])) / (v0-v[i]);
		ans = max(ans, s.t+max(td,TimeType(0)));
	}
	ans_free = min(ans_free, ans);
}
State get() {
	while (!Q.empty()) {
		State s = Q.top();
		Q.pop();
		if (besttime[s.lane][s.pos] < s.t) continue;
		return s;
	}
	return State(0.0, -1, 0.0);
}

void chg_lane(State s, int nlane) {
	if (nlane < 1 || nlane > 3) return;
	/// speeds: i=here, j=other
	int vi = v[s.lane], vj = v[nlane];
	/// space ahead
	int dd = dst[s.lane][s.pos] - 1;
	if (s.pos == L) dd = 1000100;
	
	/// check if I can go full speed and then to xj
	FORI(xj,L) if (!occ[nlane][xj]) {
		TimeType td = (TimeType(xj - s.pos) + s.t * (vj-vi)) / (v0-vj);
		TimeType tend = TimeType(1) / (v0-vi);
		//cerr << "trying " << nlane << ", " << xj << " with dt = " << td << " (td*(v0-vi) = " << (td * (v0-vi));
		//cerr << " | inequalities : " << (TimeType(0) <= td) << " " << (td * (v0-vi) <= TimeType(dd)) << "\n";
		if (TimeType(0) <= td && td * (v0-vi) <= TimeType(dd) && td <= tend) {
			add(State(s.t + td, nlane, xj));
		}
	}
	/// check if I can go to lane j and then full speed to xj
	{
		TimeType posj = TimeType(s.pos) + s.t * (vi-vj);
		int xj = posj.floor() + 1;
		//cerr << "trying just jump (pos = " << xj << "\n";
		if (xj >= 2 && xj <= L && !occ[nlane][xj-1] && !occ[nlane][xj]) {
			TimeType td = (TimeType(xj - s.pos) + s.t * (vj-vi)) / (v0-vj);
			add(State(s.t + td, nlane, xj));
		}
		/// or if I have a solution
		if (xj > L) {
			TimeType td = (TimeType(xj - s.pos) + s.t * (vj-vi)) / (v0-vj);
			add_free_car(State(s.t+td, nlane, xj));
		}
	}
	/// check if I can go to the end, wait and then to go xj
	FORI(xj,L) if (!occ[nlane][xj])  {
		TimeType td = (TimeType(xj - s.pos - dd) + s.t * (vj-vi)) / (vi-vj);
		TimeType tend = TimeType(dd) / (v0-vi);
		//cerr << "trying " << xj << " with dt = " << td << ", tend = " << tend << "\n";
		if (tend <= td) {
			add(State(s.t + td, nlane, xj));
		}
	}
}

void run() {
	FORI(i,3) FORI(j,L) besttime[i][j] = inf;
	add(State(0.0, 1, 1));
	while (true) {
		State s = get();
		//cerr << "going from lane " << s.lane << ", position " << s.pos << " at time " << s.t << "\n";
		if (s.bad()) return;
		if (!occ[s.lane][s.pos+1]) {
			//cerr << s.t << " + " << (TimeType(1) / (v0-v[s.lane])) << " = " << (s.t + TimeType(1) / (v0-v[s.lane])) << "\n";
			add(State(s.t + TimeType(1) / (v0-v[s.lane]), s.lane, s.pos+1));
		}
		if (endlane[s.lane] <= s.pos) {
			add_free_car(s);
		}
		chg_lane(s, s.lane-1);
		chg_lane(s, s.lane+1);
	}
}

int main() {
	scanf("%d%d%d%d%d", &L, &v0, &v[1], &v[2], &v[3]);
	FORI(i,3) {
		scanf(" %s", stmp);
		FOR(j,L) occ[i][j+1] = stmp[j] == '#';
	}
	L++;
	occ[3][1] = 0;
	FORI(i,3) dst[i][L+1] = 1000100;
	FORI(i,3) REPD(j,L,1) {
		if (occ[i][j]) dst[i][j] = 0;
		else dst[i][j] = dst[i][j+1] + 1;
	}
	FORI(i,3) {
		REPD(j,L,1) if (occ[i][j]) {
			endlane[i] = j+1;
			break;
		}
	}
	ans_free = inf;
	run();
	TimeType res = 0.0;
	FORI(i,3) {
		TimeType cur = inf;
		REPD(j,L,1) {
			if (!occ[i][j]) {
				cur = min(cur, besttime[i][j]);
			} else {
				break;
			}
		}
		res = max(res, cur);
		//FORI(j,L) cerr << besttime[i][j] << " ";
		//cerr << "\n";
	}
	res = min(res, ans_free);
	printf("%.12f\n", res.real());
	return 0;
}