def isok(a)
	return false if a[0]==a[2]
	(a[1]<a[0]&&a[1]<a[2]) || (a[1]>a[0]&&a[1]>a[2])
end

a=gets.split.map(&:to_i)
puts isok(a) ? :INF : (1..1e3).count{|i|isok(a.map{|e|e%i})}