      PROGRAM piyo
      IMPLICIT NONE
      integer(16) :: x,money=100,i,ans
      
      read*,x
      
      i = 0
      do while(.true.)
        i = i + 1
        money = money + money/100
        
        if( money>=x )then
          ans = i
          exit
        end if
      end do
      
      print*,ans
      
      
      
      
      END PROGRAM