#include <bits/stdc++.h>
using namespace ::std;
const long double PI = acos(-1);
const long long MOD = 1000000000 + 7;
long long gcd(long long a, long long b) { return b == 0 ? a : gcd(b, a % b); }
long long add(long long a, long long b, long long m = MOD) {
  return (a % m + b % m + 2 * m) % m;
}
long long mul(long long a, long long b, long long m = MOD) {
  return ((a % m + m) * (b % m + m)) % m;
}
long long pow_mod(long long a, long long b, long long m = MOD) {
  long long res = 1LL;
  a = a % m;
  while (b) {
    if (b & 1) res = mul(res, a, m);
    b >>= 1;
    a = mul(a, a, m);
  }
  return res;
}
long long fastexp(long long a, long long b) {
  long long res = 1LL;
  while (b) {
    if (b & 1) res = res * a;
    b >>= 1;
    a *= a;
  }
  return res;
}
int gcdExtendido(int a, int b, int *x, int *y) {
  if (a == 0) {
    *x = 0;
    *y = 1;
    return b;
  }
  int x1, y1;
  int gcd = gcdExtendido(b % a, a, &x1, &y1);
  *x = y1 - (b / a) * x1;
  *y = x1;
  return gcd;
}
int modInverso(int a, int m) {
  int x, y;
  int g = gcdExtendido(a, m, &x, &y);
  if (g != 1)
    return -1;
  else
    return (x % m + m) % m;
}
int n;
long long c1, c2;
long long f(long long x) { return c1 + c2 * (x - 1) * (x - 1); }
int main() {
  string s;
  cin >> n >> c1 >> c2;
  cin >> s;
  int adultos = 0;
  for (int i = 0; i < n; i++) {
    if (s[i] == '1') adultos++;
  }
  long long ans = LLONG_MAX;
  for (int i = 1; i <= adultos; i++) {
    long long resto = n % i;
    long long todos = n / i;
    long long q_todos = i - resto;
    long long q_extra = resto;
    long long act = q_todos * f(todos) + q_extra * f(todos + 1);
    ans = min(ans, act);
  }
  cout << ans << endl;
  return 0;
}
