package main

import (
	"fmt"
)

func main() {
	var n int
	fmt.Scan(&n)
	fmt.Println(countHit(n-1, 1, 0))
}

func countHit(need int, current int, hitMemo int) int {
	if need <= 0 {
		return hitMemo
	}
	if need <= current {
		return hitMemo + 1
	}
	return countHit(need-current, 2*current, hitMemo+1)
}