#include <bits/stdc++.h>
#define eb emplace_back
#define mt make_tuple
#define mp make_pair
#define fi first
#define se second
#define ins insert

using namespace std;
typedef long long ll;
typedef pair<int, int> pi;
typedef tuple<int, int, int> tu;
bool Mbe;

const int inf = 1e9;
const int N = 2e5 + 200;
const int M = 20;

int n, R, B, sr[N], sb[N], f[N];
int l1, l2, w1[N], w2[N], t1[N], t2[N], il[N], ir[N], tw[N];
char c[N];

struct BIT {
	int n;
	vector<int> tr;
	BIT () { }
	BIT (int _n) { n = _n, tr.resize(n + 1, -inf); }
	#define lb(x) (x & -x)
	void upd(int x, int y) { for (int i = x; i; i -= lb(i)) tr[i] = max(tr[i], y); }
	int qry(int x) { int res = -inf; for (int i = x; i <= n; i += lb(i)) res = max(res, tr[i]); return res; }
} tr[N];
vector<int> tp[N];

void cdq(int l, int r) {
	if (l == r) return;
	int md = (l + r) >> 1;
	cdq(l, md);
	for (int i = l; i <= md; i++) il[i] = i;
	for (int i = md + 1; i <= r; i++) ir[i] = i;
	sort(il + l, il + md + 1, [](int &x, int &y) { return w1[x] > w1[y]; });
	sort(ir + md + 1, ir + r + 1, [](int &x, int &y) { return w1[x] > w1[y]; });
	set<int> S;
	for (int i = l; i <= r; i++) {
		int b = i % (R + B);
		tp[b].eb(w2[i]), S.ins(b);
	}
	for (int i : S) {
		sort(tp[i].begin(), tp[i].end());
		tp[i].erase(unique(tp[i].begin(), tp[i].end()), tp[i].end());
		tr[i] = BIT(tp[i].size());
	}
	for (int i = l; i <= r; i++) {
		int b = i % (R + B);
		tw[i] = lower_bound(tp[b].begin(), tp[b].end(), w2[i]) - tp[b].begin() + 1;
	}
	// cout << l << ' ' << r << ' ' << md << '\n';
	for (int i = md + 1, j = l; i <= r; i++) {
		int x = ir[i];
		// cout << " " << x << ' ' << w1[x] << '\n';
		// cout << "! " << w1[il[j]] << '\n';
		while (j <= md && w1[il[j]] >= w1[x]) {
			int y = il[j], a = y / (R + B), b = y % (R + B);
			// cout << "  " << y << '\n';
			tr[b].upd(tw[y], f[y] - a), j++;
		}
		int a = x / (R + B), b = x % (R + B);
		f[x] = max(f[x], tr[b].qry(tw[x]) + a);
	}
	for (int i = md + 1; i <= r; i++)
		f[i] = max(f[i], f[i - 1]);
	for (int i : S) tp[i].clear();
	// cout << l << ' ' << r << '\n';
	// for (int i = 1; i <= n; i++) cout << f[i] << ' '; cout << '\n';
	cdq(md + 1, r);
}

void solve() {
    cin >> n >> R >> B >> (c + 1);
	for (int i = 1; i <= n; i++)
		sb[i] = sb[i - 1] + (c[i] == 'B'), 
		sr[i] = sr[i - 1] + (c[i] == 'R');
	for (int i = 1; i <= n; i++) {
		int a = i / (R + B);
		w1[i] = sb[i] - B * a, w2[i] = sr[i] - R * a;
		t1[++l1] = w1[i], t2[++l2] = w2[i];
	}
	sort(t1 + 1, t1 + l1 + 1), l1 = unique(t1 + 1, t1 + l1 + 1) - t1 - 1;
	sort(t2 + 1, t2 + l2 + 1), l2 = unique(t2 + 1, t2 + l2 + 1) - t2 - 1;
	for (int i = 1; i <= n; i++)
		w1[i] = lower_bound(t1 + 1, t1 + l1 + 1, w1[i]) - t1, 
		w2[i] = lower_bound(t2 + 1, t2 + l2 + 1, w2[i]) - t2;
	for (int i = 1; i <= n; i++) {
		int a = i / (R + B), b = i % (R + B);
		if (!b && sb[i] <= a * B && sr[i] <= a * R) f[i] = a; 
		f[i] = max(f[i], f[i - 1]);
	}
	// for (int i = 1; i <= n; i++) cout << f[i] << ' '; cout << '\n';
	// for (int i = 1; i <= n; i++) cout << w1[i] << ' '; cout << '\n';
	// for (int i = 1; i <= n; i++) cout << w2[i] << ' '; cout << '\n';
	cdq(1, n);
	// for (int i = 1; i <= n; i++) cout << f[i] << ' '; cout << '\n';
	cout << f[n] << '\n';
}

bool Med;
signed main() {
	ios::sync_with_stdio(0), cin.tie(0), cout.tie(0);
	cerr << (&Mbe - &Med) / 1048576.0 << " MB\n";
	#ifdef FILE
		freopen(".in", "r", stdin);
		freopen(".out", "w", stdout);
	#endif
	int T = 1;
	// cin >> T;
	while (T--) solve();
	cerr << (int)(1e3 * clock() / CLOCKS_PER_SEC) << " ms\n";
	return 0;
}