n=int(input())
m=2*n+1
x=list(map(int,input().split()))

one=[(0,1,2),(1,2,0),(2,0,1)]
two=[(2,1,0),(1,0,2),(0,2,1)]
def f(x):

    while len(x)>1:
        y=[]
        for i in range(len(x)-2):
            tup=(x[i],x[i+1],x[i+2])
            if tup in one:y.append(1)
            elif tup in two:y.append(2)
            else:y.append(0)
        x=y
    return x[0]

res=[]


for i in range(m):
    if len(res)==0:res.append(0)
    elif res[-1]==0:res.append(1)
    elif res[-1]==2:res.append(1)
    else:
        if res[-2]==0:res.append(2)
        else:res.append(0)

p=[(0,1,2),(1,2,0),(2,0,1),(2,1,0),(1,0,2),(0,2,1)]


for tup in p:
    res1=[]
    for i in range(m):
        res1.append(tup[res[i]])
    if x==res1:
        y=tuple((res1[:3]))
        if y in one:ans=1
        else:ans=2
        if n%2==0:ans=3-ans

        print(ans)

        exit()




print(0)