import os import sys from io import BytesIO, IOBase BUFSIZE = 8192 class FastIO(IOBase): newlines = 0 def __init__(self, file): self._fd = file.fileno() self.buffer = BytesIO() self.writable = "x" in file.mode or "r" not in file.mode self.write = self.buffer.write if self.writable else None def read(self): while True: b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE)) if not b: break ptr = self.buffer.tell() self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr) self.newlines = 0 return self.buffer.read() def readline(self): while self.newlines == 0: b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE)) self.newlines = b.count(b"\n")+(not b) ptr = self.buffer.tell() self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr) self.newlines -= 1 return self.buffer.readline() def flush(self): if self.writable: os.write(self._fd, self.buffer.getvalue()) self.buffer.truncate(0), self.buffer.seek(0) class IOWrapper(IOBase): def __init__(self, file): self.buffer = FastIO(file) self.flush = self.buffer.flush self.writable = self.buffer.writable self.write = lambda s:self.buffer.write(s.encode("ascii")) self.read = lambda:self.buffer.read().decode("ascii") self.readline = lambda:self.buffer.readline().decode("ascii") sys.stdin, sys.stdout = IOWrapper(sys.stdin), IOWrapper(sys.stdout) input = lambda:sys.stdin.readline().rstrip("\r\n") def solve(): n,x=map(int,input().split()) c=list(map(int,input().split())) d = [] for i in range(n): if x & (1 << c[i]) == 0: d.append(c[i]) n = len(d) c = d if n == 0: print(0) return lft=[-1]*n rgt=[-1]*n event = [] now=[0]*n for i in range(n): assert (x & (1 << c[i])) == 0 rgt[i] = x | (1 << c[i]) for j in range(c[i]): if rgt[i] >> j & 1: rgt[i] ^= 1 << j assert (rgt[i] & (1< 0 lft[i] = x for j in range(c[i]): if lft[i] >> j & 1: lft[i] ^= 1 << j lft[i] -= 1 if lft[i] < 0: lft[i] = -1 if lft[i] >= 0: event.append((lft[i],i)) now[i] = lft[i] else: now[i] = rgt[i] #print(lft,rgt) ans = 2*(max(rgt)-x) if min(lft) >= 0: ans = min(ans, 2*(x-min(lft))) ans = min(ans, 2*abs(max(now) - x) + 2*abs(min(now) - x)) event.sort() for i,j in event: now[j] = rgt[j] #print(now) ans = min(ans, 2*abs(max(now) - x) + 2*abs(min(now) - x)) print(ans) t=int(input()) for _ in range(t): solve()