n=int(input())
num=[1,4,2,8,5,7]

if n==0:
    print(0)
else:
    times=n//6
    rest=n%6

    print("0.", end='')

    for i in range(times):
        for j in range(6):
            print(num[j], end='')

    cnt=0
    while(cnt<rest):
        print(num[cnt],end='')
        cnt+=1
    print()