def fib()
	t1 = 1
	t2 = 1
	t3 = 2
	count = 2
	while (true)
		t3 = t2 + t1
		t1 = t2
		t2 = t3
		count = count+1
		if (t3.to_s().length >= 1000)
		puts count
		return
		end
	end
	return
end	
fib()