#include<stdio.h>

int main(){
  int n;
  scanf("%d", &n);

  int i = 0, fact = 1;

  while(n >= fact * 2){
    fact *= 2;
    i++;
  }
  if(n == fact){
    printf("%d\n", i);
  }else{
    printf("%d\n", i + 1);
  }

  
}