#include<bits/stdc++.h>
#define inl inline
using namespace std;
const int N=2e5+5;
int n,A,B,al,ar,bl,br,a[N],b[N],rt[N],f[N]; char s[N];
#define L (tr[p].l)
#define R (tr[p].r)
#define md (l+r>>1)
namespace T1
{
	struct TR {int l,r,w; }tr[N*400]; int tc;
	inl void AD(int &p,int l,int r,int u,int w)
	{
		!p&&(tr[p=++tc].w=-N); tr[p].w=max(w,tr[p].w);
		l<r&&(u<=md?AD(L,l,md,u,w):AD(R,md+1,r,u,w),0);
	}
	inl int QR(int p,int l,int r,int u)
	{
		return !p||r<u?-N:(l>=u?tr[p].w:max(QR(L,l,md,u),QR(R,md+1,r,u)));
	}
}
namespace T2
{
	struct TR {int l,r,w; }tr[N*20]; int tc;
	inl void AD(int &p,int l,int r,int u,int v,int w)
	{
		!p&&(p=++tc); T1::AD(tr[p].w,bl,br,v,w);
		l<r&&(u<=md?AD(L,l,md,u,v,w):AD(R,md+1,r,u,v,w),0);
	}
	inl int QR(int p,int l,int r,int u,int v)
	{
		return !p||r<u?-N:(l>=u?T1::QR(tr[p].w,bl,br,v):max(QR(L,l,md,u,v),QR(R,md+1,r,u,v)));
	}
}
int main()
{
	scanf("%d%d%d%s",&n,&A,&B,s+1); for(int i=1;i<=n;++i)
	{
		a[i+1]=a[i]+=(s[i]=='R'); b[i+1]=b[i]+=(s[i]=='B');
		al=min(al,a[i]-=i/(A+B)*A); ar=max(ar,a[i]);
		bl=min(bl,b[i]-=i/(A+B)*B); br=max(br,b[i]);
	}
	T2::AD(rt[0],al,ar,0,0,0); for(int i=1;i<=n;++i)
	{
		f[i]=max(f[i-1],i/(A+B)+T2::QR(rt[i%(A+B)],al,ar,a[i],b[i]));
		T2::AD(rt[i%(A+B)],al,ar,a[i],b[i],f[i]-i/(A+B));
	}
	printf("%d\n",f[n]); return 0;
}