import sys
input = sys.stdin.readline


X=[(0,1,2),(1,2,0),(2,0,1)]
Y=[(2,1,0),(1,0,2),(0,2,1)]




def calc(A):
    while len(A)>1:
        B=[]
        for i in range(len(A)-2):
            C=(A[i],A[i+1],A[i+2])

            if C in X:
                B.append(1)
            elif C in Y:
                B.append(2)
            else:
                B.append(0)

        A=B


    return A[0]

N=int(input())
A=list(map(int,input().split()))

flag1=1
flag2=1

for i in range(len(A)-1):
    a=A[i]
    b=A[i+1]

    k=i%4

    if 0<=k<2:

        if (b-a)%3==1:
            pass
        else:
            flag1=0
    else:
        if (b-a)%3==2:
            pass
        else:
            flag1=0
        

for i in range(N-1):
    a=A[i]
    b=A[i+1]

    k=i%4

    if 0<=k<2:

        if (b-a)%3==2:
            pass
        else:
            flag2=0
    else:
        if (b-a)%3==1:
            pass
        else:
            flag2=0

if flag1==0 and flag2==0:
    print(0)
elif flag1==1:
    if N%2==0:
        print(2)
    else:
        print(1)
else:
    if N%2==0:
        print(1)
    else:
        print(2)