t = int(input())
for i in range(t):
    n=int(input())
    q=[]
    s=list(map(int,input().split()))
    start = False
    count=0
    len=0
    max_len=0
    for j in range(n):
        if s[j]==1:
            start= True
            count+=1
            max_len=max(count,max_len)
        elif s[j]==3 and start :
            count+=1
            max_len=max(count,max_len)
        elif s[j]==2:
            q.append(count)
            max_len=count
            count=0
            start= False
        elif start :
            count+=1
            max_len=max(count,max_len)
    print(max_len)