d = gets.split.map(&:to_i).sort
if d.count(d[0]) > 1
    puts "NO"
else
    if d.count(d[1]) == 1
        if d[2] == d[3]
            puts "NO"
        else
            if d.count(d[3]) == 1
                if d[4..6].uniq == d[4..6]
                    puts "YES"
                else
                    puts "NO"
                end
            elsif d.count(d[3]) == 2
                if d[5] == d[6]
                    puts "NO"
                else
                    puts "YES"
                end
            else
                puts "NO"
            end
        end
    elsif d.count(d[1]) == 2
        if d.count(d[3]) == 1
            if d[4..6].uniq == d[4..6]
                puts "YES"
            else
                puts "NO"
            end
        elsif d.count(d[3]) == 2
            if d[5] == d[6]
                puts "NO"
            else
                puts "YES"
            end
        else
            puts "NO"
        end
    else
        puts "NO"
    end
end