public class test {
    public static void main(String[] args){
     java.util.Scanner es = new java.util.Scanner(System.in);
     while(es.hasNext()){
         int chop=es.nextInt();
         int count = 0;
         for(int i=1;i>0;i*=2,count++){      //請參考下面的規律解說   
             if(chop-i<0)break;}
         System.out.println(count);}
}}