import std.algorithm, std.container, std.conv, std.math, std.range, std.typecons, std.stdio, std.string;

auto rdsp(){return readln.splitter;}
void pick(R,T)(ref R r,ref T t){t=r.front.to!T;r.popFront;}
void readV(T...)(ref T t){auto r=rdsp;foreach(ref v;t)pick(r,v);}

void main()
{
  int s; readV(s);

  auto b = new bool[](1000001);
  b[s] = true;

  foreach (i; 2..1000002) {
    s = s%2 == 0 ? s/2 : s*3+1;
    if (b[s]) {
      writeln(i);
      return;
    }
    b[s] = true;
  }
}
