func_code_string: #include <bits/stdc++.h>   using namespace std;   const int N = 20500;   int A[N];   int n;   int B[N];   int get(int k) {     if (n / k < 3) return -1e9;     for (int i = 0; i < k; i++) B[i] = 0;     for (int i = 0; i < n; i++) B[i % k] += A[i];     int ans = -1e9;     for (int i = 0; i < k; i++) ans = max(ans, B[i]);     return ans;   }   int main() {     cin >> n;     for (int i = 0; i < n; i++) cin >> A[i];     int ans = -1e9;     for (int k = 1; k * k <= n; k++)       if (n % k == 0) ans = max(ans, max(get(k), get(n / k)));     cout << ans;     return 0;   }   