line = readlines.map(&:chomp)
 line = ["5", "1 3 4 5 7"]

n = line[0].to_i
# n = 5
arr = line[1].split(" ").map(&:to_i)
# arr = [1, 3, 4, 5, 7]

count_num = 0

(1..n).each do |num|
  if num % 2 === 1
    if arr[num] % === 1
      count_num += 1
    end
  end
end
