Problem:
Score : 300 points

Problem Statement

A sequence a_1,a_2,... ,a_n is said to be /\/\/\/ when the following conditions are satisfied:

For each i = 1,2,..., n-2, a_i = a_{i+2}.

Exactly two different numbers appear in the sequence.

You are given a sequence v_1,v_2,...,v_n whose length is even.
We would like to make this sequence /\/\/\/ by replacing some of its elements.
Find the minimum number of elements that needs to be replaced.

Constraints

2 \leq n \leq 10^5

n is even.

1 \leq v_i \leq 10^5

v_i is an integer.

Input

Input is given from Standard Input in the following format:

n
v_1 v_2 ... v_n

Output

Print the minimum number of elements that needs to be replaced.

Sample Input 1

4
3 1 3 2

Sample Output 1

1

The sequence 3,1,3,2 is not /\/\/\/, but we can make it /\/\/\/ by replacing one of its elements: for example, replace the fourth element to make it 3,1,3,1.

Sample Input 2

6
105 119 105 119 105 119

Sample Output 2

0

The sequence 105,119,105,119,105,119 is /\/\/\/.

Sample Input 3

4
1 1 1 1

Sample Output 3

2

The elements of the sequence 1,1,1,1 are all the same, so it is not /\/\/\/.

Solution in Ruby (2.3.3) (judge verdict: Time Limit Exceeded)

n = gets.to_i
v = gets.split.map(&:to_i)
e = []
o = []
v.size.times do |i|
	if i.even?
		e << v[i]
	else
		o << v[i]
	end
end
E, O = [], []
E_num, O_num = [], []

e.uniq.each do |i|
	E << e.count(i)
	E_num << i
	
end

o.uniq.each do |i|
	O << o.count(i)
	O_num << i
end

E.sort!.reverse!
O.sort!.reverse!
ans = 0

if v.uniq == 1
	puts n/2
	exit
end

if E_num[0] != O_num[0]
	ans += e.size - E[0]
	ans += o.size - O[0]
	puts ans
	exit
end



if E_num[0] == O_num[0]
	if E[0].to_i+O[1].to_i > O[0].to_i+E[1].to_i
		ans += e.size - E[0].to_i
		ans += o.size - O[1].to_i
	else
		
		ans += o.size - O[0].to_i
		ans += e.size - E[1].to_i
	end
end

puts ans