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#include <cstdio>
#include <iostream>
#include <algorithm>
#include <string>
#include <vector>
#include <limits>
#include <unordered_map>

using namespace std;

typedef vector<int> VI;
typedef long long LL;
typedef pair<int, int> PII;

#define FOR(x, b, e) for (int x = b; x <= (e); ++x)
#define FORD(x, b, e) for (int x = b; x >= (e); --x)
#define REP(x, n) for (int x = 0; x < (n); ++x)
#define VAR(v, n) __typeof(n) v = (n)
#define ALL(c) (c).begin(), (c).end()
#define SIZE(x) ((int) (x).size())
#define FOREACH(i, c) for (VAR(i, (c).begin()); i != (c).end(); ++i)
#define PB push_back
#define ST first
#define ND second
#define MP make_pair

#define INF 1000000001

int n, m;
VI S, C;

struct Game {
    int seq_no; // id of cycle
    int id;     // id in cycle
    int sb;     // sum from begining
    int sum;
    int mn;     // min from this game
};

vector<Game> G;

vector<unordered_map<int, vector<int>>> M;
//        ^           ^     ^
//        |           |     |- positions
//        |           |- game sum
//        |- # cycle

void readin()
{
    int a;
    cin >> n;
    REP(i, n) {
        cin >> a;
        S.PB(a);
    }

    string cs;
    cin >> m >> cs;
    REP(i, m) C.PB(cs[i] == 'P' ? -1 : 1);
}

int add(int i, int d)
{
    return (i + d) % m;
}

int gcd(int a, int b)
{
    while (b > 0) swap(a %= b, b);

    return a;
}

LL lcm(int a, int b)
{
    return LL(a) * LL(b) / gcd(a, b);
}

void pre_process()
{
    G.resize(m, {-1, -1, 0, 0, 0});
    int seq_no = -1;
    REP(i, m) if (G[i].seq_no == -1) {
        M.PB({});

        int k = 0;
        int s = 0;

        G[i].seq_no = ++seq_no;
        G[i].id = k;
        G[i].sb = s;

        M[seq_no][s].PB(k);

        s += C[i];
        int mn = min(0, s);
        for (int j = add(i, n); j != i; j = add(j, n)) {
            G[j].seq_no = seq_no;
            G[j].id = ++k;
            G[j].sb = s;

            M[seq_no][s].PB(k);

            s += C[j];
            mn = min(mn, s);
        }
        M[seq_no][s].PB(k);

        G[i].sum = s;
        G[i].mn = mn;

        int p = i;
        for (int j = add(i, n); j != i; j = add(j, n)) {
            mn -= C[p];
            G[j].sum = s;
            G[j].mn = mn;
            p = j;
        }

        for (auto& e: M[seq_no]) sort(ALL(e.ND));
    }
}

LL min_lost_turn(int i)
{
    int p = i % m;
    if (S[i] + G[p].mn <= 0)
        return i;

    if (G[p].sum >= 0)
        return -1;

    LL s = -G[p].sum;
    LL l = (S[i] + G[p].mn + s - 1) / s;

    return l * lcm(n, m) + i;
}

LL find_lost_turn(LL beg, int i)
{
    int k = S[i] + (beg / lcm(n, m)) * G[i % m].sum;
    if (k == 0 || k + C[beg % m] == 0) return beg;

    int p = beg % m;
    int s = k - G[p].sb;
    const auto& pos = M[G[p].seq_no][-s];

    auto it = lower_bound(ALL(pos), G[p].id);
    if (it != pos.end()) {
        beg += (*it - G[p].id) * n;
        return beg;
    }

    beg += (m - G[p].id) * n;
    beg += pos[0] * n;
    return beg;
}

LL compute()
{
    pre_process();
    vector<pair<LL, int>> v;
    REP(i, n) {
        LL mn = min_lost_turn(i);
        if (mn >= 0) v.PB(MP(mn, i));
    }

    if (v.empty()) return -1;
    sort(ALL(v));

    LL ret = numeric_limits<LL>::max();
    for (auto x : v) {
        if (x.ST >= ret) break;
        ret = min(ret, find_lost_turn(x.ST, x.ND));
    }

    return ret + 1;
}

int main()
{
    readin();
    cout << compute() << "\n";

    return 0;
}