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

using namespace std;

#define long long long
#define len length
#define re return 0
#define in(A) cin >> (A)
#define ins(A) for (int i = 0; i < A.size(); ++i) cin >> A[i];
#define ni(A) int A; in(A)
#define nis(A, N) vector<int> A(N); ins(A)
#define nis_(A, N) ni(N); nis(A, N)
#define out(A) cout << (A)
#define outs(A) for (auto x : A) cout << x << " ";
#define outre(A) out(A); re


int main() {
    nis(hs, 26);
    string s;
    in(s);
    long w = s.len();
    long h = 0;
    for (char c : s) {
        long cur = hs[c - 'a'];
        h = max(h, cur);
    }
    outre(w * h);
}