Codeforces 1107 E - Vasya and Binary String

#pragma GCC optimize(2)
#pragma GCC optimize(3)
#pragma GCC optimize(4)
#include<bits/stdc++.h>
using namespace std;
#define fi first
#define se second
#define y1 y11
#define pi acos(-1.0)
#define LL long long
//#define mp make_pair
#define DEBUG
#define pb push_back
#define ls rt<<1,l,m
#define rs rt<<1|1,m+1,r
#define ULL unsigned LL
#define pll pair<LL,LL>
#define pli pair<LL,int>
#define pii pair<int,int>
#define piii pair<pii,int>
#define pdd pair<long double,long double>
#define mem(a,b) memset(a,b,sizeof(a))
#define fio ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
#define fopen freopen("in.txt","r",stdin);freopen("out.txt","w",stout);
//head

const int N = 105;
LL dp[N][N][N];
string s;
int a[N];
LL dfs(int l,int r,int k) {
    if(l > r) return 0;
    if(l == r) return a[k+1];
    if(~dp[l][r][k]) return dp[l][r][k];
    dp[l][r][k] = dfs(l,r-1,0) + a[k+1];
    for (int i = l; i < r; i++) {
        if(s[i] == s[r]) {
            dp[l][r][k] = max(dp[l][r][k],dfs(i+1,0) + dfs(l,i,k+1));
        }
    }
    return dp[l][r][k];
}
int main() {
    fio;
    int n;
    cin >> n;
    cin >> s;
    for (int i = 1; i <= n; ++i) cin >> a[i];
    mem(dp,-1);
    cout << dfs(0,n-1,0) << endl;
    return 0;
}