size = [int(i) for i in input().split()]
word = [size[ord(c)-ord('a')] for c in input()]
print(max(word)*len(word))

public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        int n = 26;
        int h[] = new int[n];
        for(int h_i=0; h_i < n; h_i++){
            h[h_i] = in.nextInt();
        }
        String word = in.next();
        int max=0;
        int length=word.length();
        HashMap<Character,Integer> map=new HashMap<Character,Integer>();
       int i=0;
        for(char ch='a';ch<='z';ch++)
            {
            map.put(ch,h[i]);
            i++;
        }
        for(int j=0;j<length;j++)
            {
            int val=map.get(word.charAt(j));
            if(val>max)
                max=val;
        }
        System.out.println(max*length);
    }

maxHeight=0
for i in range(len(word)):
	if(h[ord(word[i])-97] > maxHeight):
		maxHeight=h[ord(word[i])-97]
print(len(word)*1*maxHeight)

function designerPdfViewer(h, word) {
    return Math.max(...word.split('').map((e) => h[e.charCodeAt(0) - 97] * word.length));
}

#include <math.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <assert.h>
#include <limits.h>
#include <stdbool.h>

int main(){
    int *h = malloc(sizeof(int) * 26);
    for(int h_i = 0; h_i < 26; h_i++){
       scanf("%d",&h[h_i]);
    }
    char* word = (char *)malloc(512000 * sizeof(char));
    scanf("%s",word);
    int max = 0;
    size_t len = strlen(word);
    for(size_t i = 0; i < len; i++) {
        int ind = word[i] - 'a';
        if(h[ind] > max) {
            max = h[ind];
        }
    }
    
    printf("%d\n", max * len);
    return 0;
}