t=int(input())
for _ in range(t):
  _=input()
  a=''.join(input().split())
  res='Yes'
  if a[0]==a[-1]:
    aa=['11','00'][int(a[0])]
    if aa not in a:
      b=[]
      p=3
      for ai in a:
        if ai!=p: b.append(ai)
        p=b[-1]
      if len(b)<=8:
        res='No'
  print(res)