C++ :

#include <algorithm>
#include <cstdio>
#include <vector>

using namespace std;

const int N = 1e5 + 5;

int n;
char s[N];
int a[N];
long long f[N];

int main() {
    scanf("%d", &n);
    scanf("%s", s + 1);
    for (int i = 1; i <= n; i++) scanf("%d", &a[i]);
    for (int i = 1; i <= n; i++) {
        int mask = 0;
        for (int j = i; j; j--) {
            int cur = 1 << (s[j] - 'a');
            if (mask & cur) break;
            mask |= cur;
            f[i] = max(f[i], f[j - 1] + a[i - j + 1]);
        }
    }
    printf("%lld\n", f[n]);
    return 0;
}