(define (read-list n)
  (cond [(zero? n) '()]
        [else (let* ([a (read)]
                     [b (read)])
                (cons (list a b) (read-list (- n 1))))]))

(define (solve lx)
  (let ([sa (apply + (map car lx))]
        [sb (apply + (map cadr lx))])
    (+ 1 (min sa sb))))

(define (main args)
  (let* ([n (read)]
         [lab (read-list (- n 1))])
    (print (solve lab)))
  0)