#include<cstdio>
#include<algorithm>
using namespace std;
void read(int &res)
{
	res=0;char ch=getchar();
	while(ch<'0'||ch>'9') ch=getchar();
	while('0'<=ch&&ch<='9') res=(res<<1)+(res<<3)+(ch^48),ch=getchar();
}
void read(char &ch)
{
	ch=getchar();
	while(ch!='R'&&ch!='W'&&ch!='B') ch=getchar();
}
const int N=2e5+100;
int n,r,b,sr[N+10],sb[N+10],f[N+10];
int id[N+10];
bool cmp(int i,int j){return sr[i]-i/(r+b)*r>sr[j]-j/(r+b)*r||(sr[i]-i/(r+b)*r==sr[j]-j/(r+b)*r&&sb[i]-i/(r+b)*b>sb[j]-j/(r+b)*b||(sr[i]-i/(r+b)*r==sr[j]-j/(r+b)*r&&sb[i]-i/(r+b)*b==sb[j]-j/(r+b)*b&&i<j));}
int rt[N+10],cnt;
struct SEG
{
	int ls,rs,maxn;
}t[N*30];
int newnode()
{
	cnt++,t[cnt].ls=t[cnt].rs=0,t[cnt].maxn=-n;
	return cnt;
}
#define mid (l+r>>1)
void update(int &p,int x,int k,int l=-n,int r=n)
{
	if(!p) p=newnode();
	t[p].maxn=max(t[p].maxn,k);
	if(l==r) return;
	if(x<=mid) update(t[p].ls,x,k,l,mid);
	else update(t[p].rs,x,k,mid+1,r);
}
int query(int p,int L,int R,int l=-n,int r=n)
{
	if(!p) return -n;
	if(L<=l&&r<=R) return t[p].maxn;
	int res=-n;
	if(L<=mid) res=max(res,query(t[p].ls,L,R,l,mid));
	if(R>mid) res=max(res,query(t[p].rs,L,R,mid+1,r));
	return res;
}
#undef mid
void solve(int l=0,int R=n)
{
	for(int i=max(l,1);i<=R;i++) f[i]=max(f[i],f[i-1]);
	if(l==R) return;
	int mid=l+R>>1;
	solve(l,mid);
	for(int i=max(l,1);i<=R;i++) f[i]=max(f[i],f[i-1]);
	id[0]=0;for(int i=l;i<=R;i++) id[++id[0]]=i;
	sort(id+1,id+1+id[0],cmp);
	for(int i=1;i<=id[0];i++)
	{
		if(id[i]<=mid) update(rt[id[i]%(r+b)],sb[id[i]]-id[i]/(r+b)*b,f[id[i]]-id[i]/(r+b));
		else f[id[i]]=max(f[id[i]],query(rt[id[i]%(r+b)],sb[id[i]]-id[i]/(r+b)*b,n)+id[i]/(r+b));
	}
	cnt=0;
	for(int i=1;i<=id[0];i++) if(id[i]<=mid) rt[id[i]%(r+b)]=0;
	solve(mid+1,R);
}
int main()
{
//	freopen("a1.in","r",stdin);
	read(n),read(r),read(b);
	for(int i=1;i<=n;i++)
	{
		char ch;read(ch);
		sr[i]=sr[i-1],sb[i]=sb[i-1];
		if(ch=='R') sr[i]++;
		if(ch=='B') sb[i]++;
	}
	solve();
	printf("%d\n",f[n]);
	return 0;
}