#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef pair<ll,ll> P;
#define REP(i,n) for(ll i=0;i<ll(n);i++)










int main(void){
	cin.tie(nullptr);  ios_base::sync_with_stdio(false);
	ll i,j;



	ll N;
	cin >> N;


	ll ans=0;
	bool f=false;
	while(1){

		if(N%2==0) N/=2;
		else N=3*N+1;

		ans++;
		if(N==1){
			f=true;
			break;
		}


	}


	if(f) cout << ans << endl;
	else cout << "infinity" << endl;











	return 0;

}