#define ULLINT  unsigned long long int
int main() {
    ULLINT fibt[93] = { 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233, 377, 610, 987, 1597, 2584, 4181, 6765, 10946, 17711, 28657, 46368, 75025, 121393, 196418, 317811, 514229, 832040, 1346269, 2178309, 3524578, 5702887, 9227465, 14930352, 24157817, 39088169, 63245986, 102334155, 165580141, 267914296, 433494437, 701408733, 1134903170, 1836311903, 2971215073, 4807526976, 7778742049, 12586269025, 20365011074, 32951280099, 53316291173, 86267571272, 139583862445, 225851433717, 365435296162, 591286729879, 956722026041, 1548008755920, 2504730781961, 4052739537881, 6557470319842, 10610209857723, 17167680177565, 27777890035288, 44945570212853, 72723460248141, 117669030460994, 190392490709135, 308061521170129, 498454011879264, 806515533049393, 1304969544928657, 2111485077978050, 3416454622906707, 5527939700884757, 8944394323791464, 14472334024676221, 23416728348467685, 37889062373143906, 61305790721611591, 99194853094755497, 160500643816367088, 259695496911122585, 420196140727489673, 679891637638612258, 1100087778366101931, 1779979416004714189, 2880067194370816120, 4660046610375530309, 7540113804746346429, 12200160415121876738 };    
    
    int db;
    cin >> db;
    for( int idb=0 ; idb < db; idb++ ) {
        string A, B;
        long n;
        cin >> A >> B;
        cin >> n;

        int itemh = A.length();

        ULLINT k = n;
        ULLINT i = 2;
        ULLINT mintah = fibt[i] * itemh;
        while( k >= mintah ) {
            i++;
            mintah = fibt[i] * itemh;
        }

        do{
            mintah = fibt[i-2] * itemh;
            if( mintah < k ) {
                    mintah = fibt[i-2] * itemh;
                    k -= mintah;
            } else {
                    i--;
            }
            i--;
        }
        while( i > 1 );

        if( k > 0 ) k--;

        if( i == 0 )
            cout << A.substr( k, 1 ) << endl;
        else
            cout << B.substr( k, 1 ) << endl;

void findInd(vector <long long> &fib, long long &n, int &j){
    //Note that fib[j] = fib[j-2] + fib[j-1]
    //We need to confirm whether n is within fib[j-2] or fib[j-1]
    if (j==0 || j==1){
        return;
    }
    if (n > fib[j-2]){
        //n is beyond fib[j-2], so we chop off fib[j-2] from n
        //And look for new n within fib[j-1]
        n -= fib[j-2];
        j--;
        findInd(fib, n, j);
    }
    else{
        //n is within fib[j-2] 
        j = j-2;
        findInd(fib, n, j);
    }
}
char findChar(string sa, string sb, long long n){
    long long la = sa.length();
    long long lb = sb.length();
    if (n <= la){
        return(sa[n-1]);
    }
    if (n <= la + lb){
        string sc = sa + sb;
        return(sc[n-1]);
    }
    vector <long long> fib;
    fib.push_back(la);
    fib.push_back(lb);
    while(fib[fib.size()-1]<n){
        fib.push_back(fib[fib.size()-2]+fib[fib.size()-1]);
    }
    int j = fib.size()-1;
    findInd(fib, n, j);
    if (j==0){
        return sa[n-1];
    }
    else{
        return sb[n-1];
    }
}

int main() {
    /* Enter your code here. Read input from STDIN. Print output to STDOUT */
    int q;
    cin >> q;
    for (int i = 1; i <= q; i++){
        string sa, sb;
        long long n;
        cin >> sa >> sb >> n;
        cout<<findChar(sa, sb, n)<<endl;
    }
    return 0;
}

    #include <bits/stdc++.h>

    using namespace std;

    typedef long long ll;
    #define fast_cin()                    \
        ios_base::sync_with_stdio(false); \
        cin.tie(NULL);                    \
        cout.tie(NULL)

    void solve()
    {
        string a,b,res;
        ll n = 0;
        cin >> a >> b >> n;
        while (res.length()<n){
            res= a+b;
            a=b;
            b=res;
        }
        cout<<res[n+1]<<endl;

    }
    int main()
    {
        fast_cin();
        ll t;
        cin >> t;
        for (int it = 1; it <= t; it++)
        {
            solve();
        }
        return 0;
    }