import kotlin.system.exitProcess
fun main(args:Array<String>) {
    val k:Long = readLine()!!.toLong()
    var s:Long = 100L
    var count:Int = 0
    while (true) {
        count++
        s = (s.toDouble() * 1.01).toLong()
        if (s >= k) {
            println(count)
            exitProcess(0)
        }
    }
}