program problemB
  implicit none


integer(8) :: X, n
integer(8) :: BNUM, RNUM, NMAX, count,MMAX, sum, A, B, C, D,multi,countA,countC
integer(8) :: money, yr
character(len=4) :: color



read(*,*) X

! yr=log(real(X)/real(100))/log(1.01)
!
! if (int(yr)==yr) then
!   n=int(yr)
! else
!   n=int(yr)+1
! end if

n=0
money=100
do while (int(money)<X)
  n=n+1
  money=money*1.01
end do

write(*,*)n


stop
end program
