// Author: Mohib Manva #include <bits/stdc++.h> using namespace std; #define ll long long #define vi vector<int> #define vll vector<long long> #define pb push_back #define mk(a,b) make_pair(a,b) #define pi pair<int,int> #define ff first #define ss second #define vpi vector<pair<int,int> > #define all(s) s.begin(),s.end() #define fast ios_base::sync_with_stdio(false) #define TC() fast;int t;scanf("%d",&t);while(t--) const int mod=(int)1e9+7; const int MAXN=10000000; int main(){ long long int ar[26]; for(int i=0;i<26;i++) cin>>ar[i]; char str[1001]; long long ma = 0; scanf("%s",str); long long ans = strlen(str); for(int i=0;str[i]!=0;i++){ ma = max(ma,ar[str[i]-'a']); } printf("%lld\n",ans*ma); return 0; }