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#include <cstdio>
#include <vector>
#include <algorithm>
using namespace std;

typedef unsigned int       u32;
typedef unsigned long long u64;
typedef signed long long   i64;

#define min(a,b) (((a)<(b))?(a):(b))
#define fprintf(...)

unsigned n, m;
unsigned B[1000000];
char     C[1000000];

u64 NWW(u64 a, u64 b)
{
    u64 ab = a*b;
    while(a != b) if(a>b) a-=b; else b-=a;
    return (ab/b);
}

int main()
{
    u32 i;
    char c;
    bool found = false;
    u64  found_min = 0;
    
    scanf("%u", &n);
    for(i=0; i<n ;++i) { scanf("%u", &B[i]); }
    scanf("%u\n", &m);
fprintf(stderr,"read m = %u\n", m);
    
    if(n==m) {
        unsigned minimum = 1e8;
        unsigned minimum_idx=0;
        for(i=0; i<n ;++i) {
            scanf("%c", &C[i]);
            if((C[i]=='P') and (B[i]<minimum)) { minimum = B[i]; minimum_idx=i; }
        }
        fprintf(stderr,"minimum %u  minimum_idx %u\n", minimum, minimum_idx);
        if(1e8==minimum) printf("-1\n");
        else             printf("%llu\n", (minimum-1LLU)*n+minimum_idx+1LLU);
    }
    else if(n > m)
    {
        for(i=0; i<m ;++i) { scanf("%c", &c); C[i]=('W'==c)?1:-1;
fprintf(stderr,"Wczytalem c=%c  C[%u]=%d\n", c, i, C[i]);
        }
            
        const u32 steps = NWW(n,m)/m - 1;
fprintf(stderr,"NWW = %llu, steps = %u\n", NWW(n,m), steps);
        for(u32 u=0; u<n ;++u)
        {
fprintf(stderr,"\tuser[%u] B=%u\n", u, B[u]);
            bool doNextIf = true;
            int balance = 0;
            int balance_min = 0;
            for(u32 s=0; s<steps ;++s)
            {
                balance += C[(s*n)%m];
                if(balance < balance_min) balance_min = balance;
fprintf(stderr,"\t\tbalance=%d  C[%u]=%d\n", balance, (s*n)%m, C[(s*n)%m]);
                if(((int)B[u]+balance)==0) {
                    if(found)
                        {
fprintf(stderr,"\t\t\t[found=true] found_min=%llu\n", (u64)s*n+u+1);
                        found_min = min(found_min, (u64)s*n+u+1); }
                    else
                        {
fprintf(stderr,"\t\t\t[found=false] found_min=%llu\n", (u64)s*n+u+1);
                        found_min = (u64)s*n+u+1; found = true; }
                    doNextIf = false;
                }
            
            }
            if(doNextIf and (balance < 0)) {
                u32 fullCycles = ((int)B[u]+balance_min) / (-1*balance);
                B[u] += fullCycles * balance;
                u64 moves = (u64)fullCycles * n * steps;
                fprintf(stderr,"\t\tNEGATIVE balance = %d fullCycles %u moves %llu  B[]=%u\n", balance, fullCycles, moves, B[u]);
                for(u32 s=0; i<4*steps ;++s)
                {
                    balance += C[(s*n)%m];
                    if(((int)B[u]+balance)==0) {
                        if(found)
                            {
fprintf(stderr,"\t\t\t[#2 found=true] found_min=%llu\n", moves+(u64)s*n+u+1);
                            found_min = min(found_min, moves+(u64)s*n+u+1); }
                        else
                            {
fprintf(stderr,"\t\t\t[#2 found=false] found_min=%llu\n", moves+(u64)s*n+u+1);
                            found_min = moves+(u64)s*n+u+1; found = true; }
                        break;
                    }
                }
            }
        }
        if(found) printf("%llu\n", found_min);
        else      printf("-1\n");
    }
    else // (n < m)
    {
        for(i=0; i<m ;++i) { scanf("%c", &c); C[i]=('W'==c)?1:-1;
fprintf(stderr,"Wczytalem c=%c  C[%u]=%d\n", c, i, C[i]);
        }
            
        const u32 steps = NWW(n,m)/n;
fprintf(stderr,"NWW = %llu, steps = %u\n", NWW(n,m), steps);
        for(u32 u=0; u<n ;++u)
        {
fprintf(stderr,"\tuser[%u] B=%u\n", u, B[u]);
            bool doNextIf = true;
            int balance = 0;
            int balance_min = 0;
            for(u32 s=0; s<steps ;++s)
            {
                balance += C[(s*n)%m];
                if(balance < balance_min) balance_min = balance;
fprintf(stderr,"\t\tbalance=%d  C[%u]=%d\n", balance, (s*n)%m, C[(s*n)%m]);
                if(((int)B[u]+balance)==0) {
                    if(found)
                        {
fprintf(stderr,"\t\t\t[found=true] found_min=%llu\n", (u64)s*n+u+1);
                        found_min = min(found_min, (u64)s*n+u+1); }
                    else
                        {
fprintf(stderr,"\t\t\t[found=false] found_min=%llu\n", (u64)s*n+u+1);
                        found_min = (u64)s*n+u+1; found = true; }
                    doNextIf = false;
                }
            
            }
            if(doNextIf and (balance < 0)) {
                u32 fullCycles = ((int)B[u]+balance_min) / (-1*balance);
                B[u] += fullCycles * balance;
                u64 moves = (u64)fullCycles * n * steps;
                fprintf(stderr,"\t\tNEGATIVE balance = %d fullCycles %u moves %llu  B[]=%u\n", balance, fullCycles, moves, B[u]);
                for(u32 s=0; i<4*steps ;++s)
                {
                    balance += C[(s*n)%m];
                    if(((int)B[u]+balance)==0) {
                        if(found)
                            {
fprintf(stderr,"\t\t\t[#2 found=true] found_min=%llu\n", moves+(u64)s*n+u+1);
                            found_min = min(found_min, moves+(u64)s*n+u+1); }
                        else
                            {
fprintf(stderr,"\t\t\t[#2 found=false] found_min=%llu\n", moves+(u64)s*n+u+1);
                            found_min = moves+(u64)s*n+u+1; found = true; }
                        break;
                    }
                }
            }
        }
        if(found) printf("%llu\n", found_min);
        else      printf("-1\n");
    }
    return 0;
}