import Foundation

private func readInt() -> [Int]{
    return readLine()!.split(separator: " ").map{Int($0)!}
}

func mainB() {
    let X = Int64(readLine()!)!
    var a: Int64 = 100
    var count = 0
    while a < X {
        a = Int64(Float(a) * 1.01)
        count += 1
    }
    
    print(count)
}

mainB()
