/* 1243 */

 #include <cstdio>

 #include <cstring>

 #include <cstdlib>

 #define MAXN 2025

 #define MAXM 256

 char type[MAXM];

 int point[MAXM];

 char bullet[MAXN];

 char kbfz[MAXN];

 int dp[MAXN][MAXN];

 int  n;

 int min(int a, int b) {

     return a<b ? a:b;

 }

 int max(int a, int b) {

     return a>b ? a:b;

 }

 int abs(int x) {

     return x< ? -x:x;

 }

 int main() {

     int i, j, k;

     int l1, l2;

     #ifndef ONLINE_JUDGE

         freopen("data.in", "r", stdin);

     #endif

     while (scanf("%d", &n) != EOF) {

         memset(point, , sizeof(point));

         scanf("%s", type);

         for (i=; i<n; ++i) {

             scanf("%d", &k);

             point[type[i]] = k;

         }

         scanf("%s", bullet+);

         scanf("%s", kbfz+);

         l1 = strlen(bullet+);

         l2 = strlen(kbfz+);

         for (i=; i<=max(l1, l2); ++i) {

             dp[][i] = ;

             dp[i][] = ;

         }

         for (i=; i<=l1; ++i) {

             for (j=; j<=l2; ++j) {

                 if (bullet[i] == kbfz[j]) {

                     dp[i][j] = dp[i-][j-] + point[bullet[i]];

                 } else  {

                     k = max(dp[i-][j], dp[i][j-]);

                     dp[i][j] = max(k, dp[i-][j-]);

                 }

             }

         }

         printf("%d\n", dp[l1][l2]);

     }

     return ;

 }