#include <bits/stdc++.h>   using namespace std;   const int INF = 0x3f3f3f3f;   const int MAX = 100005;   const int MAX1 = 1005;   const int MAX2 = 105;   const int LEN = 105;   const int BASE = 1000000000;   const double EPS = 1e-7;   const int MOD = 1000000007;   long long pow(long long a, long long b) {     long long ans = 1;     while (b) {       if (b & 1) ans = (ans * a) % MOD;       b /= 2;       a = (a * a) % MOD;     }     return ans;   }   int main(void) {     ios_base::sync_with_stdio(false);     cin.tie(NULL);     cout.tie(NULL);     ifstream in(  );     ofstream out(  );     clock_t begin = clock();     int q;     cin >> q;     while (q--) {       int n;       cin >> n;       int arr[MAX];       for (int i = (0); i < (n); ++i) {         cin >> arr[i];       }       sort(arr, arr + n);       cout << min(n - 2, arr[n - 2] - 1) <<   n ;     }     clock_t end = clock();     double esecs = double(end - begin) / CLOCKS_PER_SEC;     return 0;   }   