#include <bits/stdc++.h>
using namespace std;

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);

    int T; cin >> T;
    long long inf = 1LL<<61;
    while(T--){
        long long N,X; cin >> N >> X;
        vector<int> C(N);
        for(auto &c : C) cin >> c;

        vector<pair<long long,int>> left(N),right(N);
        for(int i=0; i<N; i++){
            int c = C.at(i);
            left.at(i).second = i;
            right.at(i).second = i;
            if(X&(1LL<<c)) continue;
            long long x = X%(1LL<<c);
            if(x == X) left.at(i) = {inf,i};
            else left.at(i) = {x+1,i};
            right.at(i) = {(1LL<<c)-x,i}; 
        }
        sort(left.rbegin(),left.rend());
        sort(right.rbegin(),right.rend());

        long long answer = inf;
        for(int i=0; i<=N; i++){
            vector<bool> need(N);
            for(int k=0; k<i; k++){
                auto &[d,p] = left.at(k);
                need.at(p) = true;
            }
            bool ng = false;
            long long now = 0;
            for(int k=i; k<N; k++){
                auto &[d,p] = left.at(k);
                if(d == inf) ng = true;
                now = d*2; break;
            }
            if(ng) continue;
            for(int k=0; k<N; k++){
                auto &[d,p] = right.at(k);
                if(need.at(p)){
                    now += d*2; break;
                }
            }
            answer = min(answer,now);
        }
        cout << answer << "\n";
    }
}