#include<bits/stdc++.h>
using ll = long long;
constexpr int inf = 1e9;
const int maxn = 2e5 + 10, maxN = maxn * 22 * 22, maxN_ = maxn * 22;
int n;
namespace T {
   int mx[maxN], ls[maxN], rs[maxN], N;
   void upd(int &k, int x, int y, int l = -n, int r = n) {
      if (! k) k = ++N, mx[k] = y;
      mx[k] = std::max(mx[k], y);
      if (l == r) return ;
      int mid = (l + r) >> 1;
      if (x <= mid) upd(ls[k], x, y, l, mid);
      else upd(rs[k], x, y, mid + 1, r);
   }
   int qry(int k, int x, int y, int l = -n, int r = n) {
      if (! k) return -inf;
      if (x <= l && r <= y) return mx[k];
      int mid = (l + r) >> 1, ans = -inf;
      if (x <= mid) ans = std::max(ans, qry(ls[k], x, y, l, mid));
      if (mid < y) ans = std::max(ans, qry(rs[k], x, y, mid + 1, r));
      return ans;
   }
}
int rt[maxn], to[maxN_], ls[maxN_], rs[maxN_], N;
void upd(int &k, int x, int y, int z, int l = -n, int r = n) {
   if (! k) k = ++N;
   T::upd(to[k], y, z);
   if (l == r) return ;
   int mid = (l + r) >> 1;
   if (x <= mid) upd(ls[k], x, y, z, l, mid);
   else upd(rs[k], x, y, z, mid + 1, r);
}
int qry(int k, int x, int y, int p, int q, int l = -n, int r = n) {
   if (! k) return -inf;
   if (x <= l && r <= y) return T::qry(to[k], p, q);
   int mid = (l + r) >> 1, ans = -inf;
   if (x <= mid) ans = std::max(ans, qry(ls[k], x, y, p, q, l, mid));
   if (mid < y) ans = std::max(ans, qry(rs[k], x, y, p, q, mid + 1, r));
   return ans;
}
int r, b;
char s[maxn];
int R[maxn], B[maxn];
int f[maxn];
int main() {
   scanf("%d%d%d%s", &n, &r, &b, s + 1);
   for (int i = 1; i <= n; i++)
      R[i] = R[i - 1] + (s[i] == 'R'), B[i] = B[i - 1] + (s[i] == 'B');
   f[0] = 0, upd(rt[0], 0, 0, 0);
   int ans = 0;
   for (int i = 1; i <= n; i++) {
      f[i] = std::max(f[i - 1], qry(rt[i % (r + b)], R[i] - (1ll * i * r) / (r + b), n, B[i] - (1ll * i * b) / (r + b), n) + i / (r + b));
      ans = std::max(ans, f[i]);
      upd(rt[i % (r + b)], R[i] - (1ll * i * r) / (r + b), B[i] - (1ll * i * b) / (r + b), f[i] - i / (r + b));
   }
   printf("%d\n", ans);
   return 0;
}