#include <bits/stdc++.h>
using namespace std;
#define rep(i,a,n) for (int i=a;i<n;i++)
#define per(i,a,n) for (int i=n-1;i>=a;i--)
#define pb push_back
#define eb emplace_back
#define mp make_pair
#define all(x) (x).begin(),(x).end()
#define fi first
#define se second
#define SZ(x) ((int)(x).size())
typedef vector<int> VI;
typedef basic_string<int> BI;
typedef long long ll;
typedef pair<int,int> PII;
typedef double db;
mt19937_64 mrand(1234); 
const ll mod=1000000007;
int rnd(int x) { return mrand() % x;}
ll powmod(ll a,ll b) {ll res=1;a%=mod; assert(b>=0); for(;b;b>>=1){if(b&1)res=res*a%mod;a=a*a%mod;}return res;}
ll gcd(ll a,ll b) { return b?gcd(b,a%b):a;}
// head

char w[1111];
int M=20;
int pw[111];
void gaoA() {
	scanf("%s",w);
	int m=strlen(w);
	VI bs;
	rep(i,0,m) {
		rep(j,0,3) {
			bs.pb((w[i]-'a')/pw[j]%3);
			bs.pb(3);
		}
	}
	int x;
	scanf("%d",&x);
	VI c(x,0);
	rep(i,0,x) scanf("%d",&c[i]);
	int t=0;
	VI d;
	rep(i,0,SZ(bs)) {
		rep(j,0,M) {
			while (c[t]%4!=bs[i]) t++;
			d.pb(c[t]); t++;
		}
	}
	//fprintf(stderr,"%d\n",t);
	assert(t<=x);
	printf("%d\n",SZ(d));
	for (auto x:d) printf("%d ",x); puts("");
}
void gaoB() {
	int x;
	scanf("%d",&x);
	VI c(x,0);
	rep(i,0,x) scanf("%d",&c[i]);
	VI bs;
	rep(i,0,x) if (i==0||c[i]%4!=c[i-1]%4) bs.pb(c[i]%4);
	assert(SZ(bs)%6==0);
	string ss;
	for (int i=0;i<SZ(bs);i+=6) {
		ss.pb(bs[i]+bs[i+2]*3+bs[i+4]*9+'a');
	}
	puts(ss.c_str());
}
char s[111];
int main() {
	pw[0]=1;
	for (int i=1;i<=3;i++) pw[i]=pw[i-1]*3;
	scanf("%s",s);
	if (s[0]=='A') gaoA();
	else gaoB();
}