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

int n,m,k,ps[N],cnt,head[N];
string a;
struct nd{int u,v;char x,y;}b[N];
struct edge{int to,nxt;}e[N<<1];
void add(int u,int v){e[++cnt]={v,head[u]},head[u]=cnt;}

int low[N],dfn[N],tot,sc,st[N],tp,bl[N];
bool vs[N];

void dfs(int u){
	low[u]=dfn[u]=++tot,st[++tp]=u,vs[u]=1;
	for(int i=head[u];i;i=e[i].nxt){
		int v=e[i].to;
		if(!dfn[v]) dfs(v),low[u]=min(low[u],low[v]);
		else if(vs[v]) low[u]=min(low[u],dfn[v]);
	}
	if(low[u]==dfn[u]){
		bl[u]=++sc;
		while(st[tp]^u) bl[st[tp]]=sc,vs[st[tp--]]=0;
		vs[st[tp--]]=0;
 	}
}

signed main(){
	ios::sync_with_stdio(0),cin.tie(0),cout.tie(0);
	cin >> n >> k >> a >> m,a=" "+a;
	for(int i=1,tt=0;i<=n;++i) if(a[i]=='x') ps[tt++]=i;
	for(int i=1;i<=m;++i) cin >> b[i].u >> b[i].x >> b[i].v >> b[i].y;
	int all=(1<<k)-1;
	for(int s=0;s<=all;++s){
		for(int i=0;i<k;++i) a[ps[i]]=((s>>i)&1?'c':'b');
		cnt=tot=sc=0;
		for(int i=1;i<=3*n;++i) head[i]=dfn[i]=0;

		for(int i=1;i<=m;++i){
			int u=b[i].u,v=b[i].v,x=b[i].x-'A',y=b[i].y-'A';
			if(x+'a'==a[u]) continue;
			if(y+'a'==a[v]){
				add(u+x*n,u+(3-x-a[u]+'a')*n);
				continue;
			}
			add(u+x*n,v+y*n),
			add(v+(3-y-a[v]+'a')*n,u+(3-x-a[u]+'a')*n);
		}
		for(int i=1;i<=3*n;++i) if(!dfn[i]) dfs(i);
		bool flg=0;
		for(int i=1;i<=n;++i){
			if(bl[i]==bl[i+n]||bl[i]==bl[i+2*n]||bl[i+n]==bl[i+2*n])
				{flg=1;break;}
		}
		if(flg) continue;
		for(int i=1;i<=n;++i){
			if(a[i]=='a') putchar(bl[i+n]<bl[i+2*n]?'B':'C');
			else if(a[i]=='b') putchar(bl[i]<bl[i+2*n]?'A':'C');
			else if(a[i]=='c') putchar(bl[i]<bl[i+n]?'A':'B');
		}
		return 0;
	}
	return puts("-1"),0;
}