#include <iostream>
#include <cstring>
#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <string>
#include <vector>
#include <list>
#include <map>
#include <queue>
#include <stack>
#include <bitset>
#include <algorithm>
#include <numeric>
#include <functional>
using namespace std;
#define LL long long
#define DB double
#define N 100100
#define esp 1e-6
#define MOD 100003
const int INF = 0x3f3f3f3f;
const LL INFF = 1LL << 60;
const DB EPS = 1e-9;
const DB OO = 1e15;
const DB PI = acos(-1.0);
char s[10],e[10], str[10];
int fac[] = {0,1,2,6,24,120,720,5040,40320};
struct tt{
char a[20];
int hash;
}u;
int vis[N][2],num[N],coutt = 0;
int kantuo(char s[])
{
int ans = 0,temp,i,j;
for(i = 0 ; i < 8 ; i++)
{
temp = 0;
for(j = i+1; j < 8 ; j++)
if(s[i]>s[j]) temp++;
ans+=temp*fac[8-i-1];
}
return ans+1;
}
void bfs()
{
char start[] = "12345678";
memset(vis,0,sizeof(vis));
int i,j,k,cur;
queue<tt>q;
strcpy(u.a,start);
u.hash = kantuo(start);
vis[u.hash][0] = N;
q.push(u);
while(!q.empty())
{
tt v = q.front();
q.pop();
//if(strcmp(v.a,e) == 0) return ;
for(i = 1 ; i <= 3 ; i++)
{
if(i == 1){
for(j = 7 ,k = 0; j >=0 ; j--) str[k++] = v.a[j];str[k] = '\0';
}else if(i == 2)
{
str[0] = v.a[3];str[1] = v.a[0];str[2] = v.a[1];str[3] = v.a[2];
str[4] = v.a[5];str[5] = v.a[6];str[6] = v.a[7];str[7] = v.a[4];str[8] = '\0';
}else {
str[0] = v.a[0];str[1] = v.a[6];str[2] = v.a[1];str[3] = v.a[3];
str[4] = v.a[4];str[5] = v.a[2];str[6] = v.a[5];str[7] = v.a[7];str[8] = '\0';
}
cur = kantuo(str);
if(vis[cur][0]) continue;
vis[cur][0] = v.hash;
vis[cur][1] = i;
strcpy(u.a,str);
u.hash = cur;
q.push(u);
}
}
}
void solve()
{
int i,k = 0;
char pos[10];
for(i = 0; i < 8 ; i++)
pos[s[i]-'0'] = i+1+'0';
for(i = 0; i < 8 ; i++)
str[i] = pos[e[i]-'0'];
int ans = kantuo(str);
while(vis[ans][0]!=N)
{
//printf("ans = %d i = %d\n",ans,vis[ans][1]);
num[k++] = vis[ans][1];
ans = vis[ans][0];
}
for(i = k -1 ; i>=0 ; i--)
if(num[i] == 1) printf("A");
else if(num[i] == 2) printf("B");
else printf("C");
printf("\n");
}
int main()
{
//freopen("out.txt","w",stdout);
bfs();
while(~scanf("%s",s))
{
scanf("%s",e);
solve();
}
return 0;
}