package Yukicoder

/**
 * Created by hichikawa on 2015/11/02.
 */
fun main(args: Array<String>) {
    fun readLineLongArray() : List<Long> {
        val str = readLine() as String
        val arrStr = str.split(" ")
        val ret = arrStr.map { it.toLong() }
        return ret
    }
    fun readLineLong() : Long {
        val str = readLine() as String
        return str.toLong()
    }
    var input = readLineLong() - 1
    var count = 0
    while (input != 0.toLong()) {
        input = input.shr(1)
        count++
    }
    println(count)
}