import sys
def input(): return sys.stdin.readline().strip()
def mapint(): return map(int, input().split())
sys.setrecursionlimit(10**9)

A = int(input())
cnt = 1
two = 2
three = 3
ans = 10**18
while 1:
    two = 2**cnt
    three = 3**cnt
    if two>=A:
        ans = min(ans, 2*cnt)
    if three>=A:
        ans = min(ans, 3*cnt)
    cnt += 1
    if two>=A and three>=A:
        break
print(ans)