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#include <iostream>
#include <vector>
#include <algorithm>
#include <set>

using namespace std;

struct Buddy
{
  Buddy( int money )
    : _money(money)
    , _cycle(-1)
    , _howfar(0)
  {}
  int _money;
  int _cycle;
  unsigned long long _howfar;
};

struct Game
{
  Game( char a )
    : _result ( 'W' == a ? 1 : -1 )
  {}

  int _result;
  vector<int> _guests;
  vector<int> _low_guests;
};

struct LessMoney
{
    bool operator() (const Buddy *x, const Buddy *y) const
    {
      return x->_money < y->_money;
    }
};

int main()
{
  ios_base::sync_with_stdio(false);

  long long N;

  cin >> N;

  vector<Buddy> team;
  team.reserve(N);
  for (int i = 0; i < N; i++)
  {
    int a;
    cin >> a;
    team.push_back(Buddy(a));
  }

  long long M;

  cin >> M;

  vector<Game> machine;
  machine.reserve(M);

  for (int i = 0; i < M; i++)
  {
    char a;
    cin >> a;
    machine.push_back( Game(a) );
  }

  for (int i = 0; i < N; i++)
  {
    machine[i%M]._guests.push_back(i);
  }

  const long long NO_RESULT = 1000000000000ULL;
  long long result = NO_RESULT;

  for (int i = 0; i < N; i++)
  {
    auto &b = team[i];
    if (-1 == b._cycle)
    {
      b._cycle = i;
      long long cyclestart = i%M;
      long long cyclepos = (cyclestart+M*N-N)%M;
      int sum = machine[cyclestart]._result;
      int minsum = 0;
      int len = 1;
      auto &startgame = machine[cyclestart];

      while (cyclestart != cyclepos)
      {
        auto &m = machine[cyclepos];
        sum += m._result;
        minsum = min(minsum, sum);

        if (!m._guests.empty())
        {
          for (auto &guest: m._guests)
          {
            auto &moveme = team[guest];
            moveme._cycle = i;

            bool hi = moveme._money + sum > 0 && moveme._money + minsum > 0;
            moveme._money += sum;
            moveme._howfar += len;
            if (hi)
              startgame._guests.push_back(guest);
            else
              startgame._low_guests.push_back(guest);

            guest = -1;
          }
          m._guests.erase (remove_if (m._guests.begin(), m._guests.end(),
                [] (const int i) { return i == -1; } ), m._guests.end());
        }

        cyclepos = (cyclepos-N+N*M)%M;
        len++;
      }

      minsum = machine[cyclepos]._result;
      cyclepos = (cyclestart+N)%M;
      int localsum = minsum;
      while (cyclepos != cyclestart)
      {
        localsum += machine[cyclepos]._result;
        minsum = min(minsum, localsum);
        cyclepos = (cyclepos+N)%M;
      }

      // sum = sum of cycle
      // minsum = minimum of cycle
      // len = length of cycle

      int target = min(sum,minsum);

      if (sum < 0)
      {
        // now everyone is either in a single position or in the last cycle
        // first, take guests from first position and add cycles

        for (auto &guest : startgame._guests)
        {
          auto &g = team[guest];
          if (g._money + target > 0) // will go over at least one more cycle
          {
            // how many cycles until target hit
            unsigned long long cycles = (g._money + target) / (-sum);
            g._money -= cycles*(-sum);
            g._howfar += cycles*len;
          }
        }
      }

		// now everyone is on the last cycle, compute the last part
		int lastlen = 0;
		int lastsum = 0;
		cyclepos = cyclestart;

		multiset<Buddy*,LessMoney> buddies = multiset<Buddy*,LessMoney>(LessMoney());
		for (auto guest : startgame._guests)
		{
				buddies.insert(&team[guest]);
		}
		startgame._guests.clear();

		// having the prio-queue, let's go through the final cycle
		while (!buddies.empty())
		{
				lastsum += machine[cyclepos]._result;
				while (!buddies.empty() && (*buddies.begin())->_money + lastsum <= 0)
				{
						auto buddy = *buddies.begin();
						buddy->_howfar += lastlen;
						buddy->_money = 0;
						buddies.erase(buddies.begin());
				}

				cyclepos = (cyclepos+N)%M;
				lastlen++;
if (lastlen>M) break;
		}

		for (auto guest : startgame._low_guests)
		{
				buddies.insert(&team[guest]);
		}

		lastlen = 1;
		lastsum = 0;
		cyclepos = cyclestart;
		while (!buddies.empty())
		{
				lastsum -= machine[cyclepos]._result;

				while (!buddies.empty() && (*buddies.rbegin())->_money + lastsum == 0)
				{
						auto buddy = *buddies.rbegin();
						buddy->_howfar -= lastlen;
						buddy->_money = 0;
						buddies.erase(--buddies.end());
				}

				cyclepos = (cyclepos+M*N-N)%M;
				lastlen++;
if (lastlen>M) break;
		}
      }
   
  }

  // finally, compute the minimum
  for (int i = 0; i < N; i++)
  {
    if (0 == team[i]._money)
    {
      long long localres = i+1 + team[i]._howfar*N;
      result = min(localres, result);
    }
  }

  cout << ((NO_RESULT == result) ? -1 : result) << endl;

  return 0;
}