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#include <bits/stdc++.h>

using namespace std;

typedef long double T;

#define st first
#define nd second
#define PII pair <int, int>

const int N = 200'007;
const T INF = 1'000'007;

const T epsilon = 1e-15;

int n, v[4];
char in[4][N];

T ans = INF;
int best_car[4];
bool can_finish[4][N];

T dist[4][N];
bool Used[4][4][N];

set <int> Free[4];
priority_queue < tuple <T, int, int> > Q;

void update_ans(int x, T y, T d)
{
    T cand_ans = d;
    for (int p = 1; p <= 3; ++p) {
        if (p == x || best_car[p] == 0) {
            continue;
        }

        T diff = v[p] * d + best_car[p] + 1 - v[x] * d - y;
        if (diff < 0) {
            continue;
        }

        cand_ans = max(cand_ans, d + diff / (v[0] - v[p]));
    }

//    printf("%d %.10Lf %.10Lf -> %.10Lf\n", x, y, d, cand_ans);
    ans = min(ans, cand_ans);
}

void check_and_push(int x, int y, T d)
{
    if (dist[x][y] > d) {
//        printf("pushes %d %d with %.10Lf\n", x, y, d);
        dist[x][y] = d;
        Q.push({-d, x, y});
    }
}

void first_move(int x, int y, int goal_x) {
    const T &d = dist[x][y];

    T respective_y = y + d * (v[x] - v[goal_x]);

    int ly = floor(respective_y + epsilon);
    int ry = ceil(respective_y - epsilon);

    if (ly >= n) {
        update_ans(goal_x, respective_y, d);
        return;
    }

    if (ly < 1) {
        return;
    }

    if (in[goal_x][ly] == '.' && in[goal_x][ry] == '.') {
        check_and_push(goal_x, ly, d + max(respective_y - ly, (T)0.) / v[x]);
        check_and_push(goal_x, ry, d + max(ry - respective_y, (T)0.) / (v[0] - v[goal_x]));
    }

    if (in[x][y + 1] == '.') {
        auto it = Free[goal_x].upper_bound(ly);
        while (it != Free[goal_x].end()) {
            T diff = *it - respective_y;
            if (diff / (v[0] - v[goal_x]) >= 1. / (v[0] - v[x])) {
                break;
            }

            check_and_push(goal_x, *it, d + diff / (v[0] - v[goal_x]));
            ++it;
        }
    }

    if (y > 1 && in[x][y - 1] == '.') {
        auto it = Free[goal_x].lower_bound(ry);

        while (it != Free[goal_x].begin()) {
            --it;

            T diff = respective_y - *it;
            if (diff / (v[x] + v[goal_x]) >= 1. / v[x]) {
                break;
            }

            check_and_push(goal_x, *it, d + diff / (v[x] + v[goal_x]));
        }
    }

    if (x < goal_x) {
        int next_y = *Free[goal_x].upper_bound(ly);
        if (next_y <= n && !Used[x][goal_x][next_y]) {
            Q.push({-d - (next_y - respective_y) / (v[x] - v[goal_x]), -(x * 3 + goal_x), y});
        }
    } else if (ry > 1) {
        int next_y = *--Free[goal_x].lower_bound(ry);
        if (next_y > 1 && !Used[x][goal_x][next_y]) {
            Q.push({-d - (respective_y - next_y) / (v[goal_x] - v[x]), -(x * 3 + goal_x), y});
        }
    }
}

int main() 
{
    scanf("%d", &n);
    scanf("%d %d %d %d", &v[0], &v[1], &v[2], &v[3]);

    ++n;
    for (int i = 1; i <= 3; ++i) {
        scanf("%s", in[i] + 1);
        in[i][n] = '.';
        in[i][1] = '.';

        for (int j = 1; j <= n; ++j) {
            dist[i][j] = INF;
            if (in[i][j] == '.') {
                Free[i].insert(j);
            } else {
                best_car[i] = j;
            }
        }

        can_finish[i][n] = true;
        for (int j = n - 1; j >= 1; --j) {
            if (in[i][j] == '#') {
                break;
            }

            can_finish[i][j] = true;
        }
        
        dist[i][1] = 0.;
        Q.push({0., i, 1});
    }

    while (!Q.empty()) {
        auto [d, type_x, y] = Q.top();
        Q.pop();

        d *= -1;

        if (type_x > 0) {
            int x = type_x;
//            printf("state %d %d with %.10Lf\n", x, y, d);
            if (can_finish[x][y]) {
                update_ans(x, y, d);
                continue;
            }
            
            if (in[x][y + 1] == '.') {
                check_and_push(x, y + 1, d + 1. / (v[0] - v[x]));
            }

            if (in[x][y - 1] == '.') {
                check_and_push(x, y - 1, d + 1. / v[x]);
            }

            for (int goal_x = 1; goal_x <= 3; ++goal_x) {
                if (abs(x - goal_x) == 1) {
                    first_move(x, y, goal_x);
                }
            }
        } else {
            type_x *= -1;
            int x = (type_x - 1) / 3, goal_x = (type_x - 1) % 3 + 1;
            int next_y = round(y + d * (v[x] - v[goal_x]));
//             printf("state %d %d -> %d %d with %.10Lf\n", x, y, goal_x, next_y, d);

            if (next_y <= 1) {
                continue;
            }

            if (next_y >= n) {
                update_ans(goal_x, next_y, d);
                continue;
            }

            if (Used[x][goal_x][next_y]) {
                continue;
            }

            Used[x][goal_x][next_y] = true;
            check_and_push(goal_x, next_y, d);

            if (x < goal_x) {
                int new_y = *Free[goal_x].upper_bound(next_y);
                Q.push({-d - (new_y - next_y) / (T)(v[x] - v[goal_x]), -(x * 3 + goal_x), y});
            } else {
                int new_y = *--Free[goal_x].find(next_y);
                Q.push({-d - (next_y - new_y) / (T)(v[goal_x] - v[x]), -(x * 3 + goal_x), y});
            }
        }
    }

    printf("%.15Lf\n", ans);
    return 0;
}