#include <bits/stdc++.h>
using namespace std;
typedef long long i64;
const int N = 1e5 + 5; 

int n, m; 
char s[N], f[N]; 
set<int> pos[N]; 

void solve(void) {
    cin >> s + 1 >> f + 1; n = strlen(s + 1); m = strlen(f + 1); 
    for (int i = 1; i <= n; ++i) pos[s[i]].insert(i); 
    int ans = 1e9, l = 0, r = 0; 
    for (int x : pos[f[1]]) {
        int i = x, flg = 1; 
        for (int j = 2; j <= m; ++j) {
            auto it = pos[f[j]].upper_bound(i); 
            if (it == pos[f[j]].end()) { flg = 0; break; }
            i = *it; 
        }
        if (flg) {
            if (i - x + 1 < ans) 
                ans = i - x + 1, l = x, r = i; 
        }
    }
    // cout << l << " " << r << "\n"; 
    for (int i = l; i <= r; ++i) cout << s[i]; 
    cout << "\n"; 
}

int main(void) {
    ios::sync_with_stdio(0); 
    int T = 1; cin >> T; 
    while (T--) solve();
    return 0;
}