// Template
#include "bits/stdc++.h"
#define rep_override(x, y, z, name, ...) name
#define rep2(i, n) for (int i = 0; i < (int)(n); ++i)
#define rep3(i, l, r) for (int i = (int)(l); i < (int)(r); ++i)
#define rep(...) rep_override(__VA_ARGS__, rep3, rep2)(__VA_ARGS__)
#define per(i, n) for (ll i = (ll)(n) - 1; i >= 0; --i)
#define all(x) (x).begin(), (x).end()
using namespace std;
using ll = long long;
constexpr int inf = 1001001001;
constexpr ll INF = 3003003003003003003LL;
template <typename T>
inline bool chmin(T &x, const T &y) {
    if (x > y) {
        x = y;
        return true;
    }
    return false;
}
template <typename T> 
inline bool chmax(T &x, const T &y) {
    if (x < y) {
        x = y;
        return true;
    }
    return false;
}
struct IOSET {
    IOSET() {
        cin.tie(nullptr);
        ios::sync_with_stdio(false);
        cout << fixed << setprecision(10);
    }
} ioset;


// Main
using ld = long double;

ld p, q, r;

ld change(ld x) {
    return x * (1 - r) + (1 - x) * r;
}

ld OR(ld x, ld y) {
    return change(1 - (1 - x) * (1 - y));
}

ld AND(ld x, ld y) {
    return change(x * y);
}

ld random(ld x, ld y) {
    return x * y * p + (1 - x * y) * q;
}


using State = string::const_iterator;
ld expr(State &state);
ld term(State &state);
ld rfactor(State &state);
ld factor(State &state);
ld val(State &state); 

ld expr(State &state) {
    ld x = term(state), res = 0;
    if (*state == 'o') {
        state += 2;
        ld y = expr(state);
        res = OR(x, y);
    } else {
        res = x;
    }
    return res;
}

ld term(State &state) {
    ld x = rfactor(state), res = 0;
    if (*state == 'a') {
        state += 3;
        ld y = term(state);
        res = AND(x, y);
    } else {
        res = x;
    }
    return res;
}

ld rfactor(State &state) {
    ld res = 0;
    if (*state == 'r') {
        state += 7;
        ld x = expr(state);
        ld y = expr(state);
        res = random(x, y);
    } else {
        res = factor(state);
    }
    return res;
}

ld factor(State &state) {
    ld res = 0;
    if (*state == '(') {
        ++state;
        res = expr(state);
        ++state;
    } else {
        res = val(state);
    }
    return res;
}

ld val(State &state) {
    if (*state == 'Y') {
        state += 3;
        return 1;
    } else {
        state += 2;
        return 0;
    }
}


int main() {
    int n;
    string s;
    cin >> n >> p >> q >> r >> s;
    State state = s.begin();
    cout << (int)(expr(state) * 100) << "\n";
}