dem23.n5

def f(N):
    s = bin(N)[2:]
    print(s)
    if s.count('1') % 2 == 0:
        s += '0'
        print(s)
        s = '10' + s[2:]
        print(s)
    else:
        s += '1'
        print(s)
        s = '11' + s[2:]
        print(s)
    return int(s,2)

f(15)
i=1
#while f(i) <= 40:
    #i += 1
#print(i)