Vasya has an array of integers of length *n*.

Vasya performs the following operations on the array: on each step he finds the longest segment of consecutive equal integers (the leftmost, if there are several such segments) and removes it. For example, if Vasya's array is [13, 13, 7, 7, 7, 2, 2, 2], then after one operation it becomes [13, 13, 2, 2, 2].

Compute the number of operations Vasya should make until the array becomes empty, i.e. Vasya removes all elements from it.
The first line contains a single integer *n* (1 ≤ *n* ≤ 200 000) — the length of the array.

The second line contains a sequence *a*<sub class="lower-index">1</sub>, *a*<sub class="lower-index">2</sub>, ..., *a*<sub class="lower-index">*n*</sub> (1 ≤ *a*<sub class="lower-index">*i*</sub> ≤ 10<sup class="upper-index">9</sup>) — Vasya's array.
In the first example, at first Vasya removes two fives at the second and third positions. The array becomes [2, 2]. In the second operation Vasya removes two twos at the first and second positions. After that the array becomes empty.

In the second example Vasya has to perform five operations to make the array empty. In each of them he removes the first element from the array.

In the third example Vasya needs three operations. In the first operation he removes all integers 4, in the second — all integers 100, in the third — all integers 2.

In the fourth example in the first operation Vasya removes the first two integers 10. After that the array becomes [50, 10, 50, 50]. Then in the second operation Vasya removes the two rightmost integers 50, so that the array becomes [50, 10]. In the third operation he removes the remaining 50, and the array becomes [10] after that. In the last, fourth operation he removes the only remaining 10. The array is empty after that.
4
2 5 5 2
2
5
6 3 4 1 5
5
8
4 4 4 2 2 100 100 100
3
6
10 10 50 10 50 50
4
1
1
1
100
45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45 45
1
1
100
1
2
1 100
2
2
1 1
1
2
100 100
1
3
1 1 1
1
3
1 1 3
2
3
1 100 1
3
3
1 5 6
3
3
10 4 10
3
3
10 10 4
2
4
100 4 56 33
4
4
1 2 2 1
2
4
1 1 1 3
2
4
5 1 1 1
2
1
4
1
2
21 21
1
3
48 48 14
2
10
69 69 69 69 69 13 69 7 69 7
6
20
15 15 71 100 71 71 15 93 15 100 100 71 100 100 100 15 100 100 71 15
14
31
17 17 17 17 29 17 17 29 91 17 29 17 91 17 29 17 17 17 29 17 17 17 17 17 17 17 17 29 29 17 17
12
43
40 69 69 77 9 10 58 69 23 9 58 51 10 69 10 89 77 77 9 9 10 9 69 58 40 10 23 10 58 9 9 77 58 9 77 10 58 58 40 77 9 89 40
38
54
34 75 90 23 47 13 68 37 14 39 48 41 42 100 19 43 68 47 13 47 48 65 45 89 56 86 67 52 87 81 86 63 44 9 89 21 86 89 20 43 43 37 24 43 77 14 43 42 99 92 49 99 27 40
53
66
79 79 49 49 79 81 79 79 79 79 81 49 49 79 49 49 79 49 49 81 81 49 49 49 81 49 49 49 81 81 79 81 49 81 49 79 81 49 79 79 81 49 79 79 81 49 49 79 79 79 81 79 49 47 49 49 47 81 79 49 79 79 79 49 49 49
34
80
80 86 39 5 58 20 66 61 32 75 93 20 57 20 20 61 45 17 86 43 31 75 37 80 92 10 6 18 21 8 93 92 11 75 86 39 53 27 45 77 20 20 1 80 66 13 11 51 58 11 31 51 73 93 15 88 6 32 99 6 39 87 6 39 6 80 8 45 46 45 23 53 23 58 24 53 28 46 87 68
78
100
3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7
3
9
1 2 2 2 1 2 2 2 1
3
12
1 1 1 49 63 63 63 19 38 38 65 27
7
7
31 31 21 21 13 96 96
4
3
1000000000 1 1000000000
3
import sys


class Record:

    def __init__(self, prev, number):
        self.prev = prev
        self.next = None
        self.number = number
        self.cnt = 1


def sort_record_by_cnt(r: Record):
    if r is None:
        return -1
    return r.cnt


class Records:

    def __init__(self):
        self.last_record = None  # type: Record
        self.records = []

    def add(self, number):
        if self.last_record is not None and self.last_record.number == number:
            self.last_record.cnt += 1
        else:
            record = Record(self.last_record, number)
            if self.last_record is not None:
                self.last_record.next = record
                self.last_record = record
            self.records.append(record)
            self.last_record = record

    def sort(self, clear=False):
        if clear:
            new_records = []
            for record in self.records:
                if record is not None and record.cnt > 0:
                    new_records.append(record)
            self.records = new_records
        self.records.sort(key=sort_record_by_cnt)

    def find_max(self):
        """ :rtype: Record """
        return self.records.pop()

    def process_next(self):
        record = self.find_max()  # type: Record
        prev = record.prev  # type: Record
        next = record.next  # type: Record
        if prev is None and next is None:
            return True
        if prev is None:
            next.prev = None
            record.cnt = 0
            return False
        if next is None:
            prev.next = None
            record.cnt = 0
            return False
        if prev.number == next.number:
            next2 = next.next  # type: Record
            prev.cnt += next.cnt
            prev.next = next.next
            next.cnt = 0
            record.cnt = 0
            if next2 is not None:
                next.prev = prev
            self.sort()
            return False
        prev.next = next
        next.prev = prev
        record.cnt = 0
        return False

    def process(self):
        cnt = 0
        while not self.process_next():
            cnt += 1
        return cnt


lines = []
for line in sys.stdin:
    lines.append(line)

n = int(lines[0].rstrip("\r\n\t "))
numbers = lines[1].rstrip("\r\n\t ").split(" ")
records = Records()
for x in numbers:
    records.add(int(x))
records.sort(False)
print(records.process() + 1)
