#include <iostream>
using namespace std;

const int maxn = 1e5+1;

typedef long long ll;

int main() {
    ll N, val[26], type[maxn], profit[maxn], ln = 0;
    bool fix[maxn];

    // input and values
    cin>> N;
    char ch;
    for (int i = 0; i < N; ++i) {
        cin>> ch;
        if (ch == '?') {
            type[i] = -1;
            fix[i] = false;
        } else {
            type[i] = int(ch-'A');
            fix[i] = true;
        }
    }
    for (int i = 0; i < 26; ++i) val[i] = 0;
    int M;
    cin>> M;
    for (int i = 0 ; i < M; ++i) {
        cin>> ch;
        cin>> val[int(ch-'A')];
    }
    for (int i = 1; i < 26; ++i) 
        if (val[i] > val[ln]) ln = i;
    // fill values
    for (int i = 0; i < N ; ++i) {
        if (type[i] == -1) {
            type[i] = ln;
        }
        profit[i] = val[type[i]];
    }

    // p
    ll p = 2;
    for (ll i=2; i<=N; ++i) {
        if (N % i == 0) {
            p = i;
            break;
        }
    }
    
    //merge
    for (ll d = N/p, divnum = 1; d > 0; d/=p, divnum++) {
        for (int i = 0; i < d; ++i) {   // every shift
            int fixType = -1;
            bool fixTypeFail = false;
            ll profitsum = 0;
            for (int j = i; j < d*p; j+=d) {     // after every step 
                profitsum += profit[j];
                if (fix[j]) {
                    if (fixType == -1) {
                        fixType = type[j];
                        if (fixType == -1) fixTypeFail = true;
                    } else {
                        if (type[j] != fixType) fixTypeFail = true;
                    } 
                }
            }
            if (fixTypeFail) {
                fix[i] = true;
                type[i] = -1;
                profit[i] = profitsum;
            } else if (fixType == -1) {
                type[i] = ln;
                profit[i] = (N/d)*val[ln]*(divnum+1);
            } else {
                fix[i] = true;
                type[i] = fixType;
                profit[i] = max(profitsum, (N/d)*val[fixType]*(divnum+1));
            }
        }
    }

    cout<< profit[0] <<endl;

    return 0;
}