import sys
input=sys.stdin.readline
def I(): return int(input())
def MI(): return map(int, input().split())
def LI(): return list(map(int, input().split()))

def main():
    mod=10**9+7
    A=I()
    p=1
    cnt=0
    ans=0
    while True:
        if p>=A:
            break
        elif p*3>=A*2:
            ans+=1
            break
        else:
            p*=2
            cnt+=1
        
    ans+=2*cnt
    print(ans)
            
    


main()