#-swank
(unless (member :child-sbcl *features*)
  (quit
   :unix-status
   (process-exit-code
    (run-program *runtime-pathname*
                 `("--control-stack-size" "256MB"
                   "--noinform" "--disable-ldb" "--lose-on-corruption" "--end-runtime-options"
                   "--eval" "(push :child-sbcl *features*)"
                   "--script" ,(namestring *load-pathname*))
                 :output t :error t :input t))))
(in-package :cl-user)
(eval-when (:compile-toplevel :load-toplevel :execute)
  (defparameter *opt*
    #+swank '(optimize (speed 3) (safety 2))
    #-swank '(optimize (speed 3) (safety 0) (debug 0)))
  #+swank (ql:quickload '(:cl-debug-print :fiveam :cp/util) :silent t)
  #+swank (use-package :cp/util :cl-user)
  #-swank (set-dispatch-macro-character
           #\# #\> (lambda (s c p) (declare (ignore c p)) `(values ,(read s nil nil t))))
  #+sbcl (dolist (f '(:popcnt :sse4)) (pushnew f sb-c:*backend-subfeatures*))
  (setq *random-state* (make-random-state t)))
#-swank (eval-when (:compile-toplevel)
          (setq *break-on-signals* '(and warning (not style-warning))))
#+swank (set-dispatch-macro-character #\# #\> #'cl-debug-print:debug-print-reader)

(macrolet ((def (b)
             `(progn (deftype ,(intern (format nil "UINT~A" b)) () '(unsigned-byte ,b))
                     (deftype ,(intern (format nil "INT~A" b)) () '(signed-byte ,b))))
           (define-int-types (&rest bits) `(progn ,@(mapcar (lambda (b) `(def ,b)) bits))))
  (define-int-types 2 4 7 8 15 16 31 32 62 63 64))

(defconstant +mod+ 1000000007)

(defmacro dbg (&rest forms)
  (declare (ignorable forms))
  #+swank (if (= (length forms) 1)
              `(format *error-output* "~A => ~A~%" ',(car forms) ,(car forms))
              `(format *error-output* "~A => ~A~%" ',forms `(,,@forms))))

(declaim (inline println))
(defun println (obj &optional (stream *standard-output*))
  (let ((*read-default-float-format*
          (if (typep obj 'double-float) 'double-float *read-default-float-format*)))
    (prog1 (princ obj stream) (terpri stream))))

;; BEGIN_INSERTED_CONTENTS
(defpackage :cp/bipartite-p
  (:use :cl)
  (:export #:bipartite-p))
(in-package :cp/bipartite-p)

;; PAY ATTENTION TO THE STACK SIZE!
(declaim (inline bipartite-p)
         (ftype (function * (values (or null simple-bit-vector) &optional)) bipartite-p))
(defun bipartite-p (graph)
  "Checks if GRAPH is bipartite and returns the vector of colorings if so,
otherwise returns NIL.

GRAPH := vector of adjacency lists"
  (declare (vector graph))
  (let* ((n (length graph))
         (visited (make-array n :element-type 'bit :initial-element 0))
         (colors (make-array n :element-type 'bit :initial-element 0)))
    (labels ((dfs (vertex color)
               (cond ((zerop (aref visited vertex))
                      (setf (aref visited vertex) 1
                            (aref colors vertex) color)
                      (if (= color 1)
                          (dolist (neighbor (aref graph vertex))
                            (dfs neighbor 0))
                          (dolist (neighbor (aref graph vertex))
                            (dfs neighbor 1))))
                     ((/= color (aref colors vertex))
                      (return-from bipartite-p nil)))))
      (dotimes (i n colors)
        (when (zerop (aref visited i))
          (dfs i 1))))))

(defpackage :cp/read-fixnum
  (:use :cl)
  (:export #:read-fixnum))
(in-package :cp/read-fixnum)

(declaim (ftype (function * (values fixnum &optional)) read-fixnum))
(defun read-fixnum (&optional (in *standard-input*))
  "NOTE: cannot read -2^62"
  (macrolet ((%read-byte ()
               `(the (unsigned-byte 8)
                     #+swank (char-code (read-char in nil #\Nul))
                     #-swank (sb-impl::ansi-stream-read-byte in nil #.(char-code #\Nul) nil))))
    (let* ((minus nil)
           (result (loop (let ((byte (%read-byte)))
                           (cond ((<= 48 byte 57)
                                  (return (- byte 48)))
                                 ((zerop byte) ; #\Nul
                                  (error "Read EOF or #\Nul."))
                                 ((= byte #.(char-code #\-))
                                  (setq minus t)))))))
      (declare ((integer 0 #.most-positive-fixnum) result))
      (loop
        (let* ((byte (%read-byte)))
          (if (<= 48 byte 57)
              (setq result (+ (- byte 48)
                              (* 10 (the (integer 0 #.(floor most-positive-fixnum 10))
                                         result))))
              (return (if minus (- result) result))))))))

;; BEGIN_USE_PACKAGE
(eval-when (:compile-toplevel :load-toplevel :execute)
  (use-package :cp/read-fixnum :cl-user))
(eval-when (:compile-toplevel :load-toplevel :execute)
  (use-package :cp/bipartite-p :cl-user))
(in-package :cl-user)

;;;
;;; Body
;;;

(defun main ()
  (let* ((n (read))
         (graph (make-array n :element-type 'list :initial-element nil)))
    (dotimes (_ (- n 1))
      (let ((u (- (read-fixnum) 1))
            (v (- (read-fixnum) 1)))
        (push u (aref graph v))
        (push v (aref graph u))))
    (let ((colors (bipartite-p graph)))
      (assert colors)
      (println (min (count 1 colors) (- n (count 1 colors)))))))

#-swank (main)

;;;
;;; Test
;;;

#+swank
(progn
  (defparameter *lisp-file-pathname* (uiop:current-lisp-file-pathname))
  (setq *default-pathname-defaults* (uiop:pathname-directory-pathname *lisp-file-pathname*))
  (uiop:chdir *default-pathname-defaults*)
  (defparameter *dat-pathname* (uiop:merge-pathnames* "test.dat" *lisp-file-pathname*))
  (defparameter *problem-url* "https://yukicoder.me/problems/no/1582"))

#+swank
(defun gen-dat ()
  (uiop:with-output-file (out *dat-pathname* :if-exists :supersede)
    (format out "")))

#+swank
(defun bench (&optional (out (make-broadcast-stream)))
  (time (run *dat-pathname* out)))

#+(and sbcl (not swank))
(eval-when (:compile-toplevel)
  (when sb-c::*undefined-warnings*
    (error "undefined warnings: ~{~A~^ ~}" sb-c::*undefined-warnings*)))

;; To run: (5am:run! :sample)
#+swank
(5am:test :sample
  (5am:is
   (equal "1
"
          (run "4
1 2
1 3
1 4
" nil)))
  (5am:is
   (equal "1
"
          (run "2
1 2
" nil)))
  (5am:is
   (equal "5
"
          (run "12
1 7
8 2
3 12
6 7
7 11
9 1
4 10
12 2
10 1
1 2
5 10
" nil))))