#include<bits/stdc++.h> using namespace std; typedef long long ll; typedef long double ld; typedef pair<ll,ll> pl; #define sl(x) scanf("%lld",&x) #define pl(x) printf("%lld\n",x) #define sf(x) sort(x.begin(),x.end(),func) #define s(x) sort(x.begin(),x.end()) #define all(v) v.begin(),v.end() #define rs(v) { s(v) ; r(v) ; } #define r(v) {reverse(all(v));} #define pb push_back #define mp make_pair #define F first #define S second #define f(i,n) for(int i=0;i<n;i++) #define rep(i,a,b) for(int i=a;i<=b;i++) const ll mod = 1000000007; const ll inf = 1e16; const ll ninf = LLONG_MIN; const ld eps = 1e-12; const ll N = 1000005; const ll LOGN = 19; const ld PI = 3.14159265358979323846; ll h[44]; int main() { ios_base::sync_with_stdio(0); f(i, 26) cin >> h[i]; string s; cin >> s; ll ans = 0; f(i, s.size()) { ans = max(ans, h[s[i] - 'a']); } cout << ans * s.size() << "\n"; return 0; }