class Onetoten
    attr_reader :b

    def initialize(b: [])
        @b = b
        @onetoten = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
    end

    def datainput
        begin
            @b = gets.chomp.split.map { |v| Integer(v) }
        rescue
            
        end
    end

    def dataoutput
        puts @onetoten - @b
    end

    def run
        datainput
        dataoutput
    end
end

if $0 == __FILE__
    Onetoten.new.run
end