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#include <iomanip>
#include <iostream>
#include <utility>
#include <algorithm>
#include <cassert>
#include <string>
#include <vector>
#include <set>
#include <map>

using namespace std;

#define ALL(x) x.begin(), x.end()
#define VAR(a,b) __typeof (b) a = b
#define IN(a) int a; cin >> a
#define IN2(a,b) int a, b; cin >> a >> b
#define REP(i,n) for (int _n=(n), i=0; i<_n; ++i)
#define FOR(i,a,b) for (int _b=(b), i=(a); i<=_b; ++i)
#define FORD(i,a,b) for (int _b=(b), i=(a); i>=_b; --i)
#define FORE(i,a) for (VAR(i,a.begin ()); i!=a.end (); ++i) 
#define PB push_back
#define MP make_pair
#define ST first
#define ND second

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

const int DBG = 0, INF = int(1e9);

VI cyc;

VI global_to_cycle_index;

struct cycle {
  VI positions;
  VI prefix_sum;
  map<int, VI> prefix_sum_to_pos;
  int sm;
};

void calc_prefix_sum_to_pos(cycle &cycle) {
  int k = cycle.positions.size(), sm = 0;
  cycle.prefix_sum.resize(k);
  REP(i,k) {
    sm += cyc[cycle.positions[i]];
    cycle.prefix_sum[i] = sm;
    cycle.prefix_sum_to_pos[sm].PB(i);
  }
  cycle.sm = sm;
}

int main() {
   ios_base::sync_with_stdio(0);
   cout.setf(ios::fixed);
   IN(n);
   VI v(n);
   FORE(it,v) cin >> *it;
   IN(m);
   cyc.resize(m);
   global_to_cycle_index.resize(m);
   REP(i,m) {
     char c; cin >> c;
     cyc[i] = c == 'W' ? 1 : -1;
   }
   vector<cycle> cycles;
   VI to_cyc(m, -1);
   REP(i,m)
     if (to_cyc[i] == -1) {
       int cyc_num = cycles.size();
       cycles.PB(cycle());
       cycle& cycle = cycles.back();
       cycle.positions.PB(i);
       to_cyc[i] = cyc_num;
       for (int j = (i + n) % m; j != i; j = (j + n) % m) {
         assert(to_cyc[j] == -1);
         to_cyc[j] = cyc_num;
         global_to_cycle_index[j] = cycle.positions.size();
         cycle.positions.PB(j);
       }
       calc_prefix_sum_to_pos(cycle);
     }
   LL res = -1;
   REP(i,n) {
     int start = i % m;
     cycle& c = cycles[to_cyc[start]];
     int pos = global_to_cycle_index[start];
     int prefix_sum = 0;
     if (pos > 0)
       prefix_sum = c.prefix_sum[pos - 1];
     int x = prefix_sum - v[i];
     if (c.prefix_sum_to_pos.count(x)) {
       VI &poss = c.prefix_sum_to_pos[x];
       VI::iterator it = lower_bound(ALL(poss), pos);
       if (it != poss.end()) {
         LL cand = i + LL(n) * (*it - pos + 1) - (n - 1);
         if (res == -1 || cand < res) res = cand;
         continue;
       }
     }
     int suffix = c.sm - prefix_sum;
     v[i] += suffix;
     assert(v[i] > 0);
     LL cur = LL(n) * (c.positions.size() - pos);
     if (c.prefix_sum_to_pos.count(-v[i])) {
       int it = c.prefix_sum_to_pos[-v[i]][0];
       cur += LL(n) * (it + 1);
       LL cand = cur - (n - i - 1);
       if (res == -1 || cand < res) res = cand;
       continue;
     }
     LL sm = c.sm;
     if (sm >= 0) continue;
     LL min_pref = c.prefix_sum_to_pos.begin()->first;
     assert(v[i] + min_pref > 0);
     int full_cycles = (v[i] + min_pref - sm - 1 ) / (-sm);
     cur += LL(full_cycles) * c.positions.size() * LL(n);
     v[i] += full_cycles * sm;
     assert(v[i] > 0);
     assert(v[i] <= -min_pref);
     assert(v[i] - sm > -min_pref);
     assert(c.prefix_sum_to_pos.count(-v[i]));
     int it = c.prefix_sum_to_pos[-v[i]][0];
     cur += LL(n) * (it + 1);
     LL cand = cur - (n - i - 1);
     if (res == -1 || cand < res) res = cand;
     continue;
   }
   cout << res << endl;
   return 0;
}