import sys
N = int(input())
if N == 5:
    print(5)
    sys.exit()
i2 = 0
k2 = N
while k2 != 0:
    k2 //= 2
    i2 += 1
i3 = 0
k3 = N
while k3 != 0:
    k3 //= 3
    i3 += 1
print(min(i2*2,i3*3))