#include<iostream>
#include<algorithm>
#include<queue>
#include<unordered_map>
using namespace std;

const int N=6;
int n;
string A,B;
string a[N],b[N];


int extend(queue<string> &q,unordered_map<string,int>&da,unordered_map<string,int>&db,string a[N],string b[N])
{
    int d=da[q.front()];
    while(q.size()&&d==da[q.front()])
    {
        auto t=q.front();
        q.pop();

        for(int i=0;i<n;i++)
            for(int j=0;j<t.size();j++)
            {
                if(t.substr(j,a[i].size())==a[i])
                {
                    string r=t.substr(0,j)+b[i]+t.substr(j+a[i].size());
                    if(da.count(r))continue;
                    if(db.count(r))return da[t]+db[r]+1;
                    da[r]=da[t]+1;
                    q.push(r);
                }
            }
    }
    return 11;
}

int bfs()
{
    if(A==B)return 0;

    queue<string> qa,qb;
    unordered_map<string,int>da,db;
    qa.push(A),qb.push(B);
    da[A]=0,db[B]=0;

    int step=0;
    while(qa.size()&&qb.size())
    {
        int t;
        if(qa.size()<qb.size()) t=extend(qa,da,db,a,b);
        else t=extend(qb,db,da,b,a);

        if(t<=10)return t;
        if(++step==10)return -1;

    }
    return -1;
}

int main()
{
    cin>>A>>B;
    while(cin>>a[n]>>b[n])n++;

    int t=bfs();
    if(t==-1)cout<<"NO ANSWER!"<<endl;
    else cout<<t<<endl;

    return 0;
}

// program procedure
// g ce
// ra dur
// am ee
// ee am