#include <map>
#include <set>
#include <list>
#include <cmath>
#include <ctime>
#include <deque>
#include <queue>
#include <stack>
#include <string>
#include <bitset>
#include <cstdio>
#include <limits>
#include <vector>
#include <climits>
#include <cstring>
#include <cstdlib>
#include <fstream>
#include <numeric>
#include <sstream>
#include <iostream>
#include <algorithm>
#include <unordered_map>

using namespace std;


int main(){
int a[26],val,i,v,answer;
    char s[10];
    for(i=0;i<26;i++)
        cin>>a[i];
    
    for(i=0;i<10;i++)
        cin>>s[i];
    
    i=0;
    
    while(s[i] != '\0')
        {
        int p=s[i];
        p=p-97;
        int q=s[i+1];
        q=q-97;
        if(a[p]<a[q])
            val=a[q];
        i++;
    }
    cout<<val;
    val=val-97;
    //cout<<val;
    v=a[val];
    //cout<<v;
    //answer=v*i;
    //cout<<answer;
    
}