#pragma comment(linker, "/STACK:10240000,10240000")

 #include <iostream>

 #include <cstdio>

 #include <algorithm>

 #include <cstdlib>

 #include <cstring>

 #include <map>

 #include <queue>

 #include <deque>

 #include <cmath>

 #include <vector>

 #include <ctime>

 #include <cctype>

 #include <set>

 #include <bitset>

 #include <functional>

 #include <numeric>

 #include <stdexcept>

 #include <utility>

 using namespace std;

 #define mem0(a) memset(a, 0, sizeof(a))

 #define mem_1(a) memset(a, -1, sizeof(a))

 #define lson l, m, rt << 1

 #define rson m + 1, r, rt << 1 | 1

 #define rep_up0(a, b) for (int a = 0; a < (b); a++)

 #define rep_up1(a, b) for (int a = 1; a <= (b); a++)

 #define rep_down0(a, b) for (int a = b - 1; a >= 0; a--)

 #define rep_down1(a, b) for (int a = b; a > 0; a--)

 #define all(a) (a).begin(), (a).end()

 #define lowbit(x) ((x) & (-(x)))

 #define constructInt4(name, a, b, c, d) name(int a = 0, int b = 0, int c = 0, int d = 0): a(a), b(b), c(c), d(d) {}

 #define constructInt3(name, a, b, c) name(int a = 0, int b = 0, int c = 0): a(a), b(b), c(c) {}

 #define constructInt2(name, a, b) name(int a = 0, int b = 0): a(a), b(b) {}

 #define pchr(a) putchar(a)

 #define pstr(a) printf("%s", a)

 #define sstr(a) scanf("%s", a)

 #define sint(a) scanf("%d", &a)

 #define sint2(a, b) scanf("%d%d", &a, &b)

 #define sint3(a, b, c) scanf("%d%d%d", &a, &b, &c)

 #define pint(a) printf("%d\n", a)

 #define test_print1(a) cout << "var1 = " << a << endl

 #define test_print2(a, b) cout << "var1 = " << a << ", var2 = " << b << endl

 #define test_print3(a, b, c) cout << "var1 = " << a << ", var2 = " << b << ", var3 = " << c << endl

 #define mp(a, b) make_pair(a, b)

 #define pb(a) push_back(a)

 typedef unsigned int uint;

 typedef long long LL;

 typedef pair<int, int> pii;

 typedef vector<int> vi;

 const int dx[] = {, , -, , , , -, -};

 const int dy[] = {-, , , , , -, , - };

 const int maxn = 1e3 + ;

 const int md = 1e9 + ;

 const int inf = 1e9 + ;

 const LL inf_L = 1e18 + ;

 const double pi = acos(-1.0);

 const double eps = 1e-;

 template<class T>T gcd(T a, T b){return b==?a:gcd(b,a%b);}

 template<class T>bool max_update(T &a,const T &b){if(b>a){a = b; return true;}return false;}

 template<class T>bool min_update(T &a,const T &b){if(b<a){a = b; return true;}return false;}

 template<class T>T condition(bool f, T a, T b){return f?a:b;}

 template<class T>void copy_arr(T a[], T b[], int n){rep_up0(i,n)a[i]=b[i];}

 int make_id(int x, int y, int n) { return x * n + y; }

 struct KMP {

     int next[];

     void GetNext(char s[]) {

         mem0(next);

         next[] = next[] = ;

         for(int i = ; s[i]; i++) {

             int j = next[i];

             while(j && s[i] != s[j]) j = next[j];

             next[i + ] = s[j] == s[i]? j +  : ;

         }

     }

 };

 KMP kmp;

 char s[], s2[], str[];

 char hsh[];

 int main() {

     //freopen("in.txt", "r", stdin);

     int T;

     cin >> T;

     rep_up0(cas, T) {

         cin >> s;

         int len = strlen(s);

         rep_up0(i, len) {

             hsh[s[i]] = 'a' + i;

         }

         cin >> s2;

         len = strlen(s2);

         int pos = (len + ) >> ;

         for (int i = ; i < pos; i ++) s2[i] = hsh[s2[i]];

         kmp.GetNext(s2);

         int res = kmp.next[len];

         while (len - res < pos) res = kmp.next[res];

         res = len - res;

         rep_up0(i, pos) str[i] = s[s2[i] - 'a'];

         for (int i = pos; i < res; i ++) str[i] = s2[i];

         for (int i = res; i <  * res; i ++) str[i] = hsh[str[i % res]];

         str[ * res] = ;

         puts(str);

     }

     return ;

 }