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## ruby_exercise_2.rb
#1. sum of even numbers
# count_even(a)
# [1,2,3] => 2
# [1,2,4] => 6


# 2. Return names with 'H' at first letter
# ['Haa', 'aa', 'kkk] => ['Haa']

## Ruby loop exercises
# 1. Returns the elements at even positions
# a = [5,6,7,3]
# => [5,7]  (5 at index 0, 7 at index 2)


# 2. Calculate the fibonaci at n th  (1,1,2,3)
# fibonaci(2) => 1
# fibonaci(4) => 3

# 3. Count how many number 4 in array
	#1. sum of even numbers
	# count_even(a)
	# [1,2,3] => 2
	# [1,2,4] => 6



	# 2. Return names with 'H' at first letter
	# ['Haa', 'aa', 'kkk] => ['Haa']
	# 1. Returns the elements at even positions
	# a = [5,6,7,3]
	# => [5,7] (5 at index 0, 7 at index 2)


	# 2. Calculate the fibonaci at n th (1,1,2,3)
	# fibonaci(2) => 1
	# fibonaci(4) => 3

	# 3. Count how many number 4 in array