import java.io.*;
import java.util.*;
import java.text.*;
import java.math.*;
import java.util.regex.*;

public class Solution {

    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        int [] arr = new int [26];
        for(int ind = 0; ind<26; ind++){
            arr[ind] = in.nextInt();
        }
        int area = 0;
        while(in.hasNext()){
            String inp = in.next().toLowerCase();
            int wid = inp.length();
            int maxHeight = 0;
            for(int i = 0; i<wid; i++){
                int index = inp.charAt(i)-'a';
                maxHeight = Math.max(maxHeight, arr[index]);
            }
            area = area + (maxHeight * wid);
        }
        System.out.println(area);
    }
}