program percent

 implicit none
 integer(8) :: year,i,k,x
 real(8) :: yen

 read*,x
 
 year=1
 yen=100
 do i=1,10000000
  yen=yen*1.01
  k=int(yen)
  if(k>=x) exit
  year=year+1
  yen=real(k)
 end do

 print*,year

end program percent

 
  