#include<bits/stdc++.h>
#define mem(x) memset(x,0,sizeof x)
using namespace std;
const int N=2e5+99;
int n,m,d,scc,cnt,top,c[N],s1[N],t1[N],dfn[N],low[N],part[N],hd[N],v[N],nxt[N],q[N];
char s[N],s2[N],t2[N],t[N];
bool vis[N],flag;
void add(int x,int y){v[++cnt]=y;nxt[cnt]=hd[x];hd[x]=cnt;}
int opp(int x){return x>n?x-n:x+n;}
int jisuan(int x,char ch)
{if(s[x]=='a')return ch=='B'?x:x+n;if(s[x]=='b'||s[x]=='c')return ch=='A'?x:x+n;if(ch=='C')return x+n;return x;
}
void tarjan(int u)
{dfn[u]=low[u]=++cnt;q[++top]=u;vis[u]=1;for(int i=hd[u];i;i=nxt[i])if(!dfn[v[i]]){tarjan(v[i]);low[u]=min(low[u],low[v[i]]);}else if(vis[v[i]])low[u]=min(low[u],dfn[v[i]]);if(dfn[u]==low[u]){part[u]=++scc;vis[u]=0;int now;do{now=q[top--];vis[now]=0;part[now]=scc;}while(now!=u);}
}
void solve()
{scc=cnt=0;mem(dfn);mem(low);mem(part);mem(hd);mem(nxt);for(int i=1;i<=m;i++)if(s[s1[i]]!='x'&&s[t1[i]]!='x'&&s[s1[i]]-32!=s2[i]){int u=jisuan(s1[i],s2[i]),v;if(s[t1[i]]-32==t2[i])add(u,opp(u));else{v=jisuan(t1[i],t2[i]);add(u,v);add(opp(v),opp(u));}}else{char S=s[s1[i]],T=s[t1[i]];int x=c[s1[i]],y=c[t1[i]];if(S=='x'&&T=='x'&&s2[i]!=t[x]){int u=jisuan(s1[i],s2[i]),v;if(t2[i]==t[y])add(u,opp(u));else{v=jisuan(t1[i],t2[i]);add(u,v);add(opp(v),opp(u));}}else if(S=='x'&&T!='x'&&s2[i]!=t[x]){int u=jisuan(s1[i],s2[i]),v;if(s[t1[i]]-32==t2[i])add(u,opp(u));else{v=jisuan(t1[i],t2[i]);add(u,v);add(opp(v),opp(u));}}else if(S!='x'&&T=='x'&&s[s1[i]]-32!=s2[i]){int u=jisuan(s1[i],s2[i]),v;if(t2[i]==t[y])add(u,opp(u));else{v=jisuan(t1[i],t2[i]);add(u,v);add(opp(v),opp(u));}}}cnt=0;for(int i=1;i<=n*2;i++)if(!dfn[i])tarjan(i);for(int i=1;i<=n;i++)if(part[i]==part[i+n])return;for(int i=1;i<=n;i++)if(part[i]<part[i+n]){if(s[i]=='a')printf("B");else if(s[i]=='b'||s[i]=='c')printf("A");else if(t[c[i]]=='A')printf("B");else printf("A");}else{if(s[i]=='a'||s[i]=='b')printf("C");else if(s[i]=='c')printf("B");else if(t[c[i]]=='A')printf("C");else printf("B");}flag=1;
}
void fact(int k)
{if(flag)return;if(k>d){solve();return;}t[k]='A';fact(k+1);t[k]='B';fact(k+1);
}
int main()
{scanf("%d%d",&n,&d);d=0;scanf("%s",s+1);for(int i=1;i<=n;i++)if(s[i]=='x')c[i]=++d;scanf("%d",&m);for(int i=1;i<=m;i++)scanf("%d %c%d %c",&s1[i],&s2[i],&t1[i],&t2[i]);fact(1);if(!flag)puts("-1");
}