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// Potyczki Algorytmiczne 2015
// runda 3
// HAZard
// Tomasz Pastusiak

#include <iostream>
#include <algorithm>
#include <functional>
#include <stack>
#include <set>
#include <cmath>
#include <vector>
#include <string>

using namespace std;

#define MAX_M_N 1000000
//#define MAX_M_N 999999
#define MAX_SECTIONS 30
#define LL long long int

//#define MAX_M_N 4
//#define MAX_SECTIONS 30

int savings[MAX_M_N];
int cycle[MAX_M_N];
pair<int, int> cycleInfo[MAX_M_N]; // <cycleID, startingPointInCycle>
pair<int, int> individualCyclesAttributes[MAX_M_N]; // <starting point in mt, base(not doubled) length in mt>

LL playerDuration[MAX_M_N]; // store how long a player can handle

int baseSections[MAX_SECTIONS];
int baseSectionsRight[MAX_SECTIONS];

class MinTree{
public:
    int tree[MAX_M_N*2*2]; // every cycle will be written doubled, thus * 2
    int n;
    int size;

    void setSize(int n){
        this->n = n;
        size = 2*n;
        for(int i=1;i<size;++i){
            tree[i] = 2*MAX_M_N; // to be safe
        }
    }

    void setValue(int position, int value){
        int node = n + position;
        tree[node] = value;

        while (node != 1) {
            node /= 2;
            if(tree[node] > value) tree[node] = value;
            else break;
        }
    }

    int getValue(int position){
        int node = n + position;
        return tree[node];
    }

    int getAreaMin(int from, int to){
        int nl = n + from, nr = n + to; // node left, node right

        int result = min(tree[nl], tree[nr]);

        while (nl / 2 != nr / 2) {
         if (nl % 2 == 0){
            result = min(result, tree[nl + 1]);
         } // if left node is left child of some parent
         if (nr % 2 == 1){
            result = min(result, tree[nr - 1]);
         } // if right node is right child of some parent
         nl /= 2; nr /= 2;
        }

        return result;
    }

    int pfflleqt(int from, int to, int value){
        int nl = n + from, nr = n + to; // node left, node right

        int sectionsCountLeft = 1;
        int sectionsCountRight = 1;
        int sectionsCount = 0;

        baseSections[0] = nl;
        baseSectionsRight[0] = nr;

        while (nl / 2 != nr / 2) {
         if (nl % 2 == 0){
            baseSections[sectionsCountLeft++] = nl + 1;
         } // if left node is left child of some parent
         if (nr % 2 == 1){
            baseSectionsRight[sectionsCountRight++] = nr - 1;
         } // if right node is right child of some parent
         nl /= 2; nr /= 2;
        }

        sectionsCount = sectionsCountLeft;

        for(int i= sectionsCountRight - 1; i >= 0 ; --i){
            baseSections[sectionsCount++] = baseSectionsRight[i];
        }
         // Sections Obtained,

        int result = -1;

        for(int i=0; i<sectionsCount; ++i){
            if(tree[baseSections[i]] <= value){
                int node = baseSections[i];
                while(node < n){
                    int leftSon = 2*node;
                    int rightSon = leftSon + 1;
                    if( tree[leftSon] <= value ) node = leftSon; // prefer left son
                    else node = rightSon;
                } // while not at ground level
                result = node - n;
                break;
            } // if section found, dig deeper
        }

        return result;
    } // pfflleqt - Position First From Left Lower or Equal Than
};

MinTree mt;

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

    int n, m;

    cin >> n;
    for(int i=0; i<n;++i){
        cin >> savings[i];
        playerDuration[i] = 0; // no need to initialise... in fact
    }

    cin >> m;
    string buffer;
    buffer.reserve(MAX_M_N);
    cin >> buffer;

    for(int i=0; i<m; ++i){
        cycle[i] = (buffer[i] == 'W' ? 1 : -1);
        cycleInfo[i] = make_pair(-1, -1);
    }

    int placeInMTtaken = 0;
    mt.setSize(2*m);

    for(int i=0; i<n; ++i){
        if(cycleInfo[i%m].first == -1){
            int positionInIC = 0;
            int positionInCycle = i%m;
            int currentPlayer = i;
            int IC_ID = i;
            int partialSum = 0;
            individualCyclesAttributes[IC_ID] = make_pair(placeInMTtaken, 1); // cycle length has to be updated later, after we find full cycle

            while(cycleInfo[positionInCycle].first == -1){
                cycleInfo[positionInCycle] = make_pair(IC_ID, positionInIC++);
                partialSum += cycle[positionInCycle];
                mt.setValue(placeInMTtaken++, partialSum);

                positionInCycle += n;
                positionInCycle %= m;
            } //

            // cycle written to MT once, TODO write it again
            int IC_length = positionInIC;
            for(int j=0; j<IC_length ;++j){
                partialSum += cycle[positionInCycle];
                mt.setValue(placeInMTtaken++, partialSum);

                positionInCycle += n;
                positionInCycle %= m;
            } // previous while loop ended, because we arrived at the beginning of IC, so we can now loop through IC again, adding it to MT again

            individualCyclesAttributes[IC_ID].second = IC_length;
        } // if there is a player without a cycle, start a individual cycle here
    } // traverse machine cycle, looking for individual cycles

    /*for(int i=0;i<n;++i){
        cout << "Player: " << i << " cycle ID: " << cycleInfo[i%m].first << " starting point: " << cycleInfo[i%m].second << " Cycle len: " << individualCyclesAttributes[cycleInfo[i%m].first].second << endl;
    }

    cout << "--------" << endl;*/

    /**for(int i=0;i<m;++i){
        cout << "Cycle position: " << i << " starting point: " << cycleInfo[i].second << " Cycle len: " << individualCyclesAttributes[cycleInfo[i].first].second << endl;
    }*/

    for(int i=0; i<n ;++i){
        pair<int, int> cycleInfoForPlayer = cycleInfo[i%m]; // <cycleID, startingPointInCycle>
        pair<int, int> cycleAttributes = individualCyclesAttributes[cycleInfoForPlayer.first]; // <starting point in mt, base(not doubled) length in mt>
        int MTstart = cycleAttributes.first + cycleInfoForPlayer.second;
        int MTend = MTstart + cycleAttributes.second - 1; // <start, end> sharp braces !

        int partialSumRelative = 0;
        if(cycleInfoForPlayer.second != 0){
            partialSumRelative = -mt.getValue(MTstart - 1);
        }

        int ICs_passed = 0;

        int worstSituation = partialSumRelative + mt.getAreaMin(MTstart, MTend);
        int IC_balance = partialSumRelative + mt.getValue(MTend);
        int moneyDistFromBankrupcy = savings[i] + worstSituation;

        if(IC_balance >= 0 && moneyDistFromBankrupcy > 0){
            playerDuration[i] = -1; // infinite duration
        }
        else{
            if(moneyDistFromBankrupcy > 0){
                int ICs_leftToBankrupcy = moneyDistFromBankrupcy/(-IC_balance);
                if(ICs_leftToBankrupcy * (-IC_balance) != moneyDistFromBankrupcy) ICs_leftToBankrupcy++; // these two lines should work like ceil

                ICs_passed = ICs_leftToBankrupcy;
                partialSumRelative += IC_balance*ICs_passed;
            } // if we are not bankrupt yet, fast forward

            int bankrupcyMoment = mt.pfflleqt(MTstart, MTend, -savings[i] - partialSumRelative) - MTstart;
            playerDuration[i] = i + ICs_passed*(LL)cycleAttributes.second*(LL)n + bankrupcyMoment*(LL)n + 1; // i players before me, (ICs_passed*cycleLen) times all players played before me, ...
            // use long longs here?
        } // else, we are going bankrupt, but when?
    } // for each player, calculate duration

    LL smallestDuration = -1;

    for(int i=0; i<n; ++i){
        if(smallestDuration == -1) smallestDuration = playerDuration[i];
        else if(playerDuration[i] != -1) smallestDuration = min(smallestDuration, playerDuration[i]);
    }

cout << smallestDuration << endl;

    return 0;
}