func_code_string: #include <bits/stdc++.h>   using namespace std;   string s;   long long int dp[510][501];   long long int solve(long long int l, long long int r) {     if (dp[l][r] != -1) {       return dp[l][r];     }     if (l > r) return 0;     long long int a = 1 + solve(l + 1, r);     for (long long int i = l + 1; i <= r; i++) {       if (s[i] != s[l]) continue;       a = min(a, solve(l + 1, i - 1) + solve(i, r));     }     dp[l][r] = a;     return a;   }   int main() {     ios_base::sync_with_stdio(false);     cin.tie(NULL);     long long int n, i;     cin >> n;     cin >> s;     memset(dp, -1, sizeof dp);     cout << solve(0, s.size() - 1);   }   