#include<bits/stdc++.h>
using namespace std;
namespace my_std{
	#define ll long long
	#define bl bool
	ll my_pow(ll a,ll b,ll mod){
		ll res=1;
		if(!b) return 1;
		while(b){
			if(b&1) res=(res*a)%mod;
			a=(a*a)%mod;
			b>>=1;
		}
		return res;
	}
	ll qpow(ll a,ll b){
		ll res=1;
		if(!b) return 1;
		while(b){
			if(b&1) res*=a;
			a*=a;
			b>>=1;
		}
		return res;
	}
	#define db double
	#define pf printf
	#define pc putchar
	#define fr(i,x,y) for(register ll i=(x);i<=(y);i++)
	#define pfr(i,x,y) for(register ll i=(x);i>=(y);i--)
	#define go(u) for(ll i=head[u];i;i=e[i].nxt)
	#define enter pc('\n')
	#define space pc(' ')
	#define fir first
	#define sec second
	#define MP make_pair
	#define il inline
	#define inf 8e18
	#define random(x) rand()*rand()%(x)
	#define inv(a,mod) my_pow((a),(mod-2),(mod))
	il ll read(){
		ll sum=0,f=1;
		char ch=0;
		while(!isdigit(ch)){
			if(ch=='-') f=-1;
			ch=getchar();
		}
		while(isdigit(ch)){
			sum=sum*10+(ch^48);
			ch=getchar();
		}
		return sum*f;
	}
	il void write(ll x){
		if(x<0){
			x=-x;
			pc('-');
		}
		if(x>9) write(x/10);
		pc(x%10+'0');
	}
	il void writeln(ll x){
		write(x);
		enter;
	}
	il void writesp(ll x){
		write(x);
		space;
	}
}
using namespace my_std;
ll n,m,r,c,col[1010][1010],v[1010][1010],cnt[1000010],tot=0;
char s[1010][1010];
bl ck(ll x,ll y){
	if(x>=1&&x<=n&&y>=1&&y<=m) if(s[x][y]!='@'&&!col[x][y]) return 1;
	return 0;
}
void dfs(ll x,ll y,ll cl,ll w){
	cnt[cl]++;
	col[x][y]=cl;
	v[x][y]=w;
	if(ck(x+r,y+c)) dfs(x+r,y+c,cl,w^1);
	if(ck(x+r,y-c)) dfs(x+r,y-c,cl,w^1);
	if(ck(x-r,y+c)) dfs(x-r,y+c,cl,w^1);
	if(ck(x-r,y-c)) dfs(x-r,y-c,cl,w^1);
	if(ck(x+c,y+r)) dfs(x+c,y+r,cl,w^1);
	if(ck(x+c,y-r)) dfs(x+c,y-r,cl,w^1);
	if(ck(x-c,y+r)) dfs(x-c,y+r,cl,w^1);
	if(ck(x-c,y-r)) dfs(x-c,y-r,cl,w^1);
}
int main(){
	n=read();
	m=read();
	r=read();
	c=read();
	fr(i,1,n) scanf("%s",s[i]+1);
	fr(i,1,n){
		fr(j,1,m){
			if(!col[i][j]&&s[i][j]!='@'){
				tot++;
				dfs(i,j,tot,0);
			}
		}
	}
	ll cola,va,colb,vb;
	fr(i,1,n){
		fr(j,1,m){
			if(s[i][j]=='A'){
				cola=col[i][j];
				va=v[i][j];
			}
			if(s[i][j]=='B'){
				colb=col[i][j];
				vb=v[i][j];
			}
		}
	}
	if(cnt[cola]==1) pf("Bob");
	else if(cola==colb&&va!=vb) pf("Bob");
	else pf("Alice");
}