#include<bits/stdc++.h>
using namespace std;
// #define int long long
#define rep(i,j,k) for(int i=(j);i<=(k);i++)
#define per(i,j,k) for(int i=(j);i>=(k);i--)
#define pb push_back
#define mp make_pair
#define fi first
#define se second
typedef vector<int> vi;
typedef pair<int,int> pi;

typedef long long ll;

const int N=2e5+5, M=N*20, inf=1e9;
struct Set{
    map<int,int> st;
    void ins(int x,int y){
        auto it=st.upper_bound(x);
        while(it!=st.begin() && prev(it)->se<=y){
            it=st.erase(prev(it));
        }
        if(it==st.end() || it->se<y){
            st[x]=y;
        }
    }
    int qry(int x){
        auto it=st.lower_bound(x);
        return (it==st.end()? -inf: it->se);
    }
};
int sn, sm;
struct sgt{
    #define mid ((l+r)/2)

    Set w[M];
    int s[M][2];
    int rt[N], tot;
    void ins(int &d,int l,int r,int nx,int ny,int nw){
        if(!d){
            d=++tot;
        }
        w[d].ins(ny, nw);
        if(l==r){
            return;
        }
        nx<=mid? ins(s[d][0], l, mid, nx, ny, nw): ins(s[d][1], mid+1, r, nx, ny, nw);
    }
    int qry(int d,int l,int r,int nx,int ny){
        if(!d){
            return -inf;
        }
        if(l>=nx){
            return w[d].qry(ny);
        }
        if(nx>mid){
            return qry(s[d][1], mid+1, r, nx, ny);
        }
        return max(qry(s[d][0], l, mid, nx, ny), qry(s[d][1], mid+1, r, nx, ny));
    }

    #undef mid
}T;
vi getlis(vector<ll> A, int &sz){
    vector<ll> lis=A;
    sort(lis.begin(), lis.end());
    lis.erase(unique(lis.begin(), lis.end()), lis.end());
    sz=lis.size();
    vi res;
    for(ll x:A){
        res.pb(upper_bound(lis.begin(), lis.end(), x)-lis.begin());
    }
    return res;
}
void solve(){
    int n,r,b; cin>>n>>r>>b;
    string s; cin>>s;
    s=' '+s;
    vector<ll> _R(n+1, 0), _B(n+1, 0);
    rep(i,1,n){
        _R[i]=_R[i-1]+(s[i]=='R'? r+b: 0)-r;
        _B[i]=_B[i-1]+(s[i]=='B'? r+b: 0)-b;
    }
    vi R=getlis(_R, sn);
    vi B=getlis(_B, sm);
    vi f(n+1, 0);
    T.ins(T.rt[0], 1, sn, R[0], B[0], 0);
    rep(i,1,n){
        int get=T.qry(T.rt[i%(r+b)], 1, sn, R[i], B[i]);
        f[i]=get+i/(r+b);
        f[i]=max(f[i], f[i-1]);
        T.ins(T.rt[i%(r+b)], 1, sn, R[i], B[i], f[i]-i/(r+b));
    }
    int ans=f[n];
    cout<<ans<<'\n';
}
signed main(){
    #ifndef ONLINE_JUDGE
    assert(freopen(".in","r",stdin));
    // assert(freopen(".out","w",stdout));
    #endif
    ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);

    solve();
}