#include<bits/stdc++.h>
#define up(j,k,i) for(i=j;i<k;i++)
#define down(j,k,i) for(i=j;i>k;i--)
#define pp(n) printf("%lld\n",n)
#define is(n) scanf("%lld",&n)
#define ss(s) scanf("%s",s)
#define cool 0
#define pb push_back
#define mp make_pair
#define F first
#define S second
#define f(i) cout<<i<<endl;
#define pll pair<lld,lld> 
typedef long double ld;
typedef long long int lld;
using namespace std;
const lld M =1e9+7;
int main()
{
    lld i,l;
    string s;
    map<char,lld> m;
    up(0,26,i)
    {
        is(l);
        m['a'+i]=l;
    }
    cin>>s;
    l=s.size();
    lld w,h=0;
    up(0,l,i)
    {
        h=max(m[s[i]],h);
        
    }
    w=h*l;
    cout<<w<<endl;
    return 0;
}