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#include <cstdio>
#include <algorithm>
#include <cmath>
#include <vector>

using namespace std;

typedef long long int LL;

const int mxn = (int)1e6 + 7;

#define PII pair<int,int>
#define st first
#define nd second
#define pb push_back
#define mp make_pair

int n, m;
int d;
int kiesz[mxn];
int cykl[mxn];
int when[mxn];
int help[mxn];
int potega[mxn];
int RMQ[2*mxn][25];
vector <int> V[mxn];
vector <int> sumy_pref[mxn];
vector <int> sumy_suf[mxn];
vector <int> min_pref[mxn];
vector <int> min_suf[mxn];

int nwd(int a, int b){
	if(b == 0)
		return a;
	return nwd(b, a%b);
}

int rmq(int from, int to){
	if(to < from)
		return 0;
    return min(RMQ[from][potega[to-from+1]], RMQ[1+to-1<<potega[to-from+1]][potega[to-from+1]]);
}

int minimum(int i, int x){
	int result = min(rmq(x, m/d) - sumy_pref[i][x-1], sumy_suf[i][x] + rmq(0, x-1));
	return result;
}

void LICZ_RMQ(int i){
	
	for(int j=0; j<=m/d; ++j)
		RMQ[j][0] = sumy_pref[i][j];
	
	int k = 1;
	for(int j=1; j<=20; ++j){
		for(int ii=0; ii<=m/d-k; ++ii)
			RMQ[ii][j] = min(RMQ[ii][j-1], RMQ[ii+k][j-1]);
		k*=2;
	}
	
}

int LICZ(int i, int from, int to){
	return rmq(from, to) - sumy_pref[i][from-1];
}

int licz(int i, int from, int to){
	return rmq(0, to) + sumy_suf[i][from];
}

int BS(int i, int x, int value){
	int pocz = x;
	int kon = m/d;
	while(pocz < kon){
		int sred = (pocz + kon)/2;
		if(LICZ(i, x, sred) + value <= 0)
			kon = sred;
		else
			pocz = sred+1;
	}
	
	if(LICZ(i, x, pocz) + value <= 0)
		return pocz - x + 1;
	
	pocz = 1;
	kon = x-1;
	
	while(pocz < kon){
		int sred = (pocz + kon)/2;
		if(licz(i, x, sred) + value <= 0)
			kon = sred;
		else
			pocz = sred+1;
	}
	
	return pocz + (m/d) - x + 1;
	
}

int main() {
	
	scanf("%d", &n);
	for(int i=1; i<=n; ++i)
		scanf("%d", &kiesz[i]);
	
	scanf("%d", &m);
	for(int i=1; i<=m; ++i){
		char znak;
		scanf(" %c", &znak);
		if(znak == 'W')
			cykl[i] = 1;
		else
			cykl[i] = -1;
	}
	
	int xd=2;
	int ile_dodac = 0;
	for(int i=1; i<=m; ++i){
		if(i == xd){
			ile_dodac++;
			xd*=2;
		}
		potega[i] = ile_dodac;
	}
	
	d = nwd(n, m);
	
	for(int i=1; i<=d; ++i){
		int x = m/d;
		int now = i;
		
		V[i].pb(0);
		for(int j=1; j<=x; ++j){
			V[i].pb(cykl[now]);
			when[now] = j;
			now+= d;
			now--;
			now%= m;
			now++;
		}
		
		for(int j=1; j<=x; ++j)
			help[j] = help[j-1] + V[i][j];
		for(int j=0; j<=x; ++j)
			sumy_pref[i].pb(help[j]);
		
		for(int j=x; j>=0; --j)
			help[j] = help[j+1] + V[i][j];
		for(int j=0; j<=x; ++j)
			sumy_suf[i].pb(help[j]);
		
		for(int j = 0; j <= x; ++j)
			help[j] = min(help[j-1], sumy_pref[i][j]);
		for(int j=0; j<=x; ++j)
			min_pref[i].pb(help[j]);
		
		for(int j=x; j>=0; --j)
			help[j] = min(help[j+1], sumy_suf[i][j]);
		for(int j=0; j<=x; ++j)
			min_suf[i].pb(help[j]);

	}

	LL result = -1;

	for(int i=1; i<=d; ++i){
		LICZ_RMQ(i);
		for(int j = i; j<=n; j+=d){
		
			int x = m/d;
			int mn = minimum(i, when[(j-1)%m + 1]);
			int ile = kiesz[j];
			int add = 0;

			ile+=mn;
			if(ile > 0 && sumy_pref[i][x] >= 0)
				continue;
		    
			if(ile <= 0)
				add = 0;
			else
				add = (ile - sumy_pref[i][x] - 1)/-sumy_pref[i][x];
			ile-=mn;
			ile+=add*sumy_pref[i][x];
			LL wynik = (LL)BS(i, when[(j-1)%m + 1], ile);
			wynik=(wynik-1LL)*(LL)n + (LL)j;
			wynik+=(LL)add * (LL)x * (LL)n;
		
			if(result == -1LL)
				result = wynik;
			else
				result = min(wynik, result);
		}

	}
	
	printf("%lld\n", result);
	
	return 0;
}