#include <bits/stdc++.h>
#define LL long long
using namespace std;
const int NR = 2e5 + 5;

int n, nB, nR;

struct SG1 {
    struct Node {
        int ls, rs, mx;
    }t[NR * 300];
    int tot;
    int query(int p, int l, int r, int ql, int qr) {
        if (!p) return -1e9;
        if (ql <= l && qr >= r) return t[p].mx;
        int mid = l + r >> 1, mx = -1e9;
        if (ql <= mid) mx = max(mx, query(t[p].ls, l, mid, ql, qr));
        if (qr > mid) mx = max(mx, query(t[p].rs, mid + 1, r, ql, qr));
        return mx;
    }
    void modify(int &p, int l, int r, int i, int x) {
        if (!p) p = ++tot, t[p].mx = -1e9;
        t[p].mx = max(t[p].mx, x);
        if (l == r) return;
        int mid = l + r >> 1;
        if (i <= mid) modify(t[p].ls, l, mid, i, x);
        else modify(t[p].rs, mid + 1, r, i, x);
    }
}sg1;
struct SG2 {
    struct Node {
        int ls, rs, id;
    }t[NR << 5];
    int tot;
    int query(int p, int l, int r, int ql, int qr, int x, int y) {
        if (!p) return -1e9;
        if (ql <= l && qr >= r) return sg1.query(t[p].id, 1, nR, x, y);
        int mid = l + r >> 1, res = -1e9;
        if (ql <= mid) res = max(res, query(t[p].ls, l, mid, ql, qr, x, y));
        if (qr > mid) res = max(res, query(t[p].rs, mid + 1, r, ql, qr, x, y));
        return res;
    }
    void modify(int &p, int l, int r, int x, int y, int val) {
        if (!p) p = ++tot;
        sg1.modify(t[p].id, 1, nR, y, val);
        if (l == r) return;
        int mid = l + r >> 1;
        if (x <= mid) modify(t[p].ls, l, mid, x, y, val);
        else modify(t[p].rs, mid + 1, r, x, y, val);
    }
}sg2;
int rt[NR];
int lsh_b[NR], lsh_r[NR], R[NR], B[NR];

int main() {
    ios::sync_with_stdio(0), cin.tie(0);
    int r, b; cin >> n >> r >> b;
    string s; cin >> s, s = ' ' + s;
    for (int i = 1; i <= n; i++) {
        R[i] = R[i - 1], B[i] = B[i - 1];
        if (s[i] == 'R') ++R[i];
        if (s[i] == 'B') ++B[i];
        lsh_b[i] = B[i] - i / (r + b) * b;
        lsh_r[i] = R[i] - i / (r + b) * r;
    }
    sort(lsh_b + 1, lsh_b + n + 2), sort(lsh_r + 1, lsh_r + n + 2);
    nB = unique(lsh_b + 1, lsh_b + n + 2) - lsh_b - 1;
    nR = unique(lsh_r + 1, lsh_r + n + 2) - lsh_r - 1;
    int x = lower_bound(lsh_b + 1, lsh_b + nB + 1, 0) - lsh_b;
    int y = lower_bound(lsh_r + 1, lsh_r + nR + 1, 0) - lsh_r;
    sg2.modify(rt[0], 1, nB, x, y, 0);
    int lst = 0;
    for (int i = 1; i <= n; i++) {
        int x = B[i] - i / (r + b) * b, y = R[i] - i / (r + b) * r, p = i % (r + b);
        x = lower_bound(lsh_b + 1, lsh_b + nB + 1, x) - lsh_b;
        y = lower_bound(lsh_r + 1, lsh_r + nR + 1, y) - lsh_r;
        lst = max(lst, sg2.query(rt[p], 1, nB, x, nB, y, nR) + i / (r + b));
        sg2.modify(rt[p], 1, nB, x, y, lst - i / (r + b));
    }
    cout << lst << '\n';
    cerr << (double)clock() / CLOCKS_PER_SEC << endl;
    return 0;
}