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#include <cstdio>
#include <algorithm>
using namespace std;

const int maxN = 1000000, maxTreeSize = (1 << 22), INFint = 1000000000;
const long long INFLL = 1000000000000000000LL;

struct UglyTree
{
    private:

    int offset, query_begin, query_end, sum[maxTreeSize], min_on_segment[maxTreeSize], max_on_segment[maxTreeSize];
    int target, proper_base_vertex;
    int current_pref, res;
    bool found;

    void check_base_vertices(int v, int left, int right)
    {
        if (found or (query_begin >= right) or (query_end <= left))
            return;

        if ((query_begin <= left) and (query_end >= right))
        {
            if ((min_on_segment[v] <= target) and (max_on_segment[v] >= target))
            {
                proper_base_vertex = v;
                found = 1;
            }

            else
                target -= sum[v];

            return;
        }

        check_base_vertices(v * 2, left, (left + right) / 2);
        check_base_vertices(v*2+1, (left + right) / 2, right);
    }

    void look_min_pref(int v, int left, int right)
    {
        if ((query_begin >= right) or (query_end <= left))
            return;

        if ((query_begin <= left) and (query_end >= right))
        {
            res = min(res, current_pref + min_on_segment[v]);
            current_pref += sum[v];
            return;
        }

        look_min_pref(v * 2, left, (left + right)  / 2);
        look_min_pref(v*2+1, (left + right) / 2, right);
    }

    public:

    void reinitialize(int n, int* T)
    {
        offset = 1;

        while (offset < n)
            offset *= 2;

        for (int i = offset; i < offset + n; i++)
            sum[i] = min_on_segment[i] = max_on_segment[i] = T[i - offset];

        for (int i = offset + n; i < offset * 2; i++)
        {
            sum[i] = 0;
            min_on_segment[i] = INFint;
            max_on_segment[i] = -INFint;
        }

        for (int i=offset-1; i>0; i--)
        {
            sum[i] = sum[i * 2] + sum[i*2+1];
            min_on_segment[i] = min(min_on_segment[i * 2], sum[i * 2] + min_on_segment[i*2+1]);
            max_on_segment[i] = max(max_on_segment[i * 2], sum[i * 2] + max_on_segment[i*2+1]);
        }
    }

    int first_index_with_such_sum(int begin, int end, int wanted_sum)
    {
        query_begin = begin + offset;
        query_end = end + offset;
        target = wanted_sum;
        found = 0;

        check_base_vertices(1, offset, offset * 2);

        int v = proper_base_vertex;

        while (v < offset)
        {
            if ((min_on_segment[v * 2] <= target) and (max_on_segment[v * 2] >= target))
                v *= 2;

            else
            {
                target -= sum[v * 2];
                v = v * 2 + 1;
            }
        }

        return (v + 1 - offset);
    }

    int min_of_prefs(int begin, int end)
    {
        query_begin = begin + offset;
        query_end = end + offset;
        current_pref = 0;
        res = INFint;

        look_min_pref(1, offset, offset * 2);

        return res;
    }
};

int in[maxN], T[maxN], indexes[maxN * 2], values[maxN * 2], min_pref[maxN];
bool vis[maxN];
long long res[maxN];

UglyTree tree;

int main()
{
    int n;
    scanf ("%d", &n);

    for (int i=0; i<n; i++)
        scanf ("%d", &in[i]);

    int m;
    scanf ("%d", &m);

    char W[maxN + 1];
    scanf ("%s", W);

    for (int i=0; i<m; i++)
        T[i] = (W[i] == 'W') ? 1 : -1;

    for (int i=0; i<m; i++)
    {
        if (vis[i])
            continue;

        int cycle_length = 0, cycle_sum = 0;

        int v = i;

        while (!vis[v])
        {
            cycle_sum += T[v];

            indexes[cycle_length] = v;
            values[cycle_length++] = T[v];

            vis[v] = 1;
            v = (v + n) % m;
        }

        for (int j = cycle_length; j < cycle_length * 2; j++)
            values[j] = values[j - cycle_length];

        tree.reinitialize(cycle_length * 2, values);

        for (int j=0; j<cycle_length; j++)
            min_pref[j] = tree.min_of_prefs(j, j + cycle_length);

        for (int k=0; k<cycle_length; k++)
        {
            for (int j=indexes[k]; j<n; j+=m)
            {
                if (cycle_sum >= 0)
                {
                    if (in[j] + min_pref[k] > 0)
                        res[j] = INFLL;

                    else
                        res[j] = tree.first_index_with_such_sum(k, k + cycle_length, -in[j]) - k;

                    continue;
                }

                int tail = cycle_sum - min_pref[k];
                int amount_of_cycles = max(0, (in[j] - 1 - tail) / -cycle_sum);

                in[j] += amount_of_cycles * cycle_sum;
                res[j] = (long long)amount_of_cycles * cycle_length + tree.first_index_with_such_sum(k, k + cycle_length, -in[j]) - k;

                //printf("amount: %d, tail: %d, res: %lld\n", amount_of_cycles, tail, res[j]);
            }
        }
    }

    long long result = INFLL;

    for (int i=0; i<n; i++)
    {
        if (res[i] == INFLL)
            continue;

        result = min(result, (long long)(res[i] - 1) * n + i + 1);
    }

    printf("%lld\n", (result == INFLL) ? -1LL : result);

    return 0;
}