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#include <cstdio>
#include <vector>
using namespace std;
vector <int> cycle[1000005];
vector < int > przyn[1000005];
vector < long long > pref;
vector < pair < long long, int > > best_forward, best_pref;
int where[1000005], cycle_pos[1000005];
long long koszt[1000005], bandyta[1000005];
int n,m, next_nr = 1;
int forward(int a){
    return (a-1+n) % m + 1;
}
int back(int a){
    return (a-1-n+m) % m + 1;
}
inline long long min(long long a, long long b){
    if (a < b)
        return a;
    return b;
}
inline long long max(long long a, long long b){
    if (a > b)
        return a;
    return b;
}
inline long long ceil(long long a, long long b){
    if (a % b == 0){
        return a/b;
    }
    else {
        return a/b + 1;
    }
}
void process(int st){
    int start = st;
    cycle[next_nr].push_back(0);
    int cycle_count = 1;
    do {
        cycle[next_nr].push_back(start);
        where[start] = next_nr;
        cycle_pos[start] = cycle_count;
        start = forward(start);
        cycle_count++;
    } while (start != st);
}

pair <long long,int> drzewo[4000005];
void add_tree(int pos, int s, int cs, int ce, pair <long long,int> v){
    if ((s == cs) && (s == ce)){
        drzewo[pos] = v;
    }
    else if (s <= (cs+ce)/2){
        add_tree(pos*2, s, cs, (cs+ce)/2, v);
        if (drzewo[pos*2].first <= drzewo[pos*2+1].first)
            drzewo[pos] = drzewo[pos*2];
        else
            drzewo[pos] = drzewo[pos*2+1];
    }
    else {
        add_tree(pos*2+1, s, (cs+ce)/2+1, ce, v);
        if (drzewo[pos*2].first <= drzewo[pos*2+1].first)
            drzewo[pos] = drzewo[pos*2];
        else
            drzewo[pos] = drzewo[pos*2+1];
    }
}

pair <long long, int> get_tree(int pos, int s, int e, int cs, int ce, long long v){
    //printf(":: %d %d %d %d %d\n", pos, s, e, cs, ce);
    if ((s == cs) && (e == ce)){
        if (drzewo[pos].first + v > 0){
            return make_pair(0,-1);
        }
        else if (s == e){
            return drzewo[pos];
        }
        else {
            pair <long long, int> t = get_tree(pos*2, s, (cs+ce)/2, cs, (cs+ce)/2, v);
            if (t.second == -1){
                return get_tree(pos*2+1, (cs+ce)/2+1, e, (cs+ce)/2+1, ce, v);
            }
            else {
                return t;
            }
        }
    }
    else if ((s <= (cs+ce)/2) && (e <= (cs+ce)/2)){
        return get_tree(pos*2, s, e, cs, (cs+ce)/2, v);
    }
    else if ((s > (cs+ce)/2) && (e > (cs+ce)/2)){
        return get_tree(pos*2+1, s, e, (cs+ce)/2+1, ce, v);
    }
    else {
        pair <long long, int> t = get_tree(pos*2, s, (cs+ce)/2, cs, (cs+ce)/2, v);
        if (t.second == -1){
            return get_tree(pos*2+1, (cs+ce)/2+1, e, (cs+ce)/2+1, ce, v);
        }
        else {
            return t;
        }
    }
}

int main(){
    scanf("%d", &n);
    for (int i = 1; i <= n; i++){
        scanf("%lld", &koszt[i]);
    }
    scanf("%d", &m);
    for (int i = 1; i <= m; i++){
        char t;
        scanf(" %c", &t);
        if (t == 'W'){
            bandyta[i] = 1;
        }
        else {
            bandyta[i] = -1;
        }
        //printf("%lld ", bandyta[i]);
    }
    //printf("\n");
    for (int i = 1; i <= m; i++){
        if (where[i] == 0){
            process(i);
            next_nr++;
        }
    }
    for (int i = 1; i <= n; i++){
        przyn[ where[ (i-1) % m + 1 ] ].push_back(i);
    }
    long long best = 1000000000000000005LL;
    //printf("a %d\n", next_nr);
    for (int i = 1; i < next_nr; i++){
            /*for (int j = 0; j < przyn[i].size(); j++){
                printf("%d ", przyn[i][j]);
            }
            printf("\n");*/
        pref.push_back(0);
        best_pref.push_back(make_pair(0,0));
        for (int j = 1; j < cycle[i].size(); j++){
               // printf("%d ", cycle[i][j]);
            pref.push_back(bandyta[ cycle[i][j] ] + pref[pref.size()-1]);
        }
        //printf("\n");
        for (int j = 1; j < cycle[i].size(); j++){
            if (pref[j] < best_pref[j-1].first){
                best_pref.push_back(make_pair(pref[j],j));
            }
            else {
                best_pref.push_back(best_pref[best_pref.size()-1]);
            }
        }
        /*for (int j = 0; j < cycle[i].size(); j++){
            printf("%lld ", pref[j]);
        }
        printf("\n");
        for (int j = 0; j < cycle[i].size(); j++){
            printf("%lld ", best_pref[j]);
        }
        printf("\n");*/
        best_forward.resize( cycle[i].size() );
        best_forward[ cycle[i].size()-1 ] = make_pair(pref[ cycle[i].size()-1 ], cycle[i].size()-1);
        for (int j = cycle[i].size()-2; j >= 1; j--){
            if (pref[j] < best_forward[j+1].first){
                best_forward[j] = make_pair(pref[j], j);
            }
            else {
                best_forward[j] = best_forward[j+1];
            }
        }
        /*for (int j = 1; j < cycle[i].size(); j++){
            printf("%lld ", best_forward[j]);
        }
        printf("\n");*/
        for (int j = 1; j < cycle[i].size(); j++){
            add_tree(1, j, 1, cycle[i].size()-1, make_pair(pref[j],j));
        }
    //printf("a\n");
        for (int k = 0; k < przyn[i].size(); k++){
            long long round = 1000000000000000005LL;
            int j = cycle_pos[ (przyn[i][k] - 1) % m + 1 ];
            //printf("%d %d\n", przyn[i][k], j);
            //printf("wuwuzela %d %d\n", (przyn[i][k] - 1) % m + 1, j);
            if (best_forward[j].first - pref[j-1] + koszt[ przyn[i][k] ] <= 0){
                round = min(round, 0);
            }
            else if (pref[ cycle[i].size()-1 ] < 0){
                round = min(round, ceil(((best_forward[j].first - pref[j-1]) + koszt[ przyn[i][k] ]), (-pref[ cycle[i].size()-1 ])));
            }
            //printf("zeta\n");
            if (round < 1000000000000000005LL){
                long long kos = koszt[ przyn[i][k] ] + round * pref[ cycle[i].size()-1 ] - pref[j-1];
                //printf("ww2 %lld %lld\n", kos, round);
                pair < long long, int > t = get_tree(1, j, cycle[i].size()-1, 1, cycle[i].size()-1, kos);
                //printf("cc2 %lld %d\n", t.first, t.second);
                //printf("dupa2 %d %lld %d %d", przyn[i][k], round * (cycle[i].size()-1), t.second, j);
                if (t.second != -1){
                    best = min(best, przyn[i][k] + n * (round * (cycle[i].size()-1) + t.second - j));
                }

            }
            //printf("buta\n");
        }
        //printf("b\n");
        for (int k = 0; k < przyn[i].size(); k++){
            long long round = 1000000000000000005LL;
            int j = cycle_pos[ (przyn[i][k] - 1) % m + 1 ];
            if (pref[ cycle[i].size()-1 ] + best_pref[j-1].first - pref[j-1] + koszt[ przyn[i][k] ] <= 0){
                    //printf("c\n");
                round = min(round, 0);
            }
            else if (pref[ cycle[i].size()-1 ] < 0){
                    //printf("d %lf\n", ceil((pref[ cycle[i].size()-1 ] + best_pref[j-1].first - pref[j-1] + koszt[ cycle[i][j] ]) / (double)(-pref[ cycle[i].size()-1 ])));
                round = min(round, ceil((pref[ cycle[i].size()-1 ] + best_pref[j-1].first - pref[j-1] + koszt[ przyn[i][k] ]), (-pref[ cycle[i].size()-1 ])));
            }
            if ((round < 1000000000000000005LL) && (j > 1)){
                long long kos = koszt[ przyn[i][k] ] + round * pref[ cycle[i].size()-1 ] + pref[ cycle[i].size()-1 ] - pref[j-1];
                pair < long long, int > t = get_tree(1, 1, j-1, 1, cycle[i].size()-1, kos);
                //printf("wwwwwwwwwwwwwwww0 %lld %lld %lld %d %d\n", kos, round, t.first, t.second, j);
                if (t.second != -1){
                    best = min(best, przyn[i][k] + n * (round * (cycle[i].size()-1) + t.second + (cycle[i].size()-1) - j));
                    //printf("ww1 %lld %lld\n", kos, round);
                    //printf("cc1 %lld %d\n", t.first, t.second);
                    //printf("dupa1 %d %lld %d %d", przyn[i][k], round * (cycle[i].size()-1), t.second, j);
                }
            }
        }
        best_pref.clear();
        best_forward.clear();
        pref.clear();
    }
    if (best == 1000000000000000005LL){
        printf("-1\n");
    }
    else {
        printf("%lld\n", best);
    }
}