=begin
Suppose I have the following Array of tuples

[ ['a',1], ['b',2], ['c','3' ]
How can I convert this to a Hash?

{ 'a' => 1, 'b' => 2, 'c' => 3}
Once I've written the algorithm, how would I make it generally available throughout my Ruby application?

=end
def convert_to_hash(arr)
	final_arr = []
	arr.map{|el| final_arr << {el[0] => el[1]}}
	return final_arr
end


puts convert_to_hash([ ['a',1], ['b',2], ['c','3' ]]).inspect

#--------------------------------------------------------------------------------------------------------------

=begin
Reverse a String in Ruby
Write an iterative function to reverse a string.
Do the same thing as a recursive function.
=end

class String
	def reverse_me
		chars.to_a.inject([]){|arr, el| arr.unshift(el)}.join('')
	end
end

puts "hello world".reverse_me


=begin
print multiplication table in Ruby
=end
x = (1..12)
y = (1..12)
y.each do |j|
    x.each {|i| print "%-3d" % (i*j)}
    print "\n"
end

#--------------------------------------------------------------------------------------------------------------
=begin
print sum of numbers within given file
=end
puts File.open('file_with_integers').each_line.inject(0){|sum, line| sum + line.to_i}

#--------------------------------------------------------------------------------------------------------------

=begin
Print odd numbers in Ruby

Write function to print the odd numbers from 1 to 99
=end

puts [*1..99].collect{|el| el if el.odd?}.compact

#-------------------------------------------------------------------------------------------------------------
=begin
find next palindrome
=end

def next_palindrome(n)
	 n += 1
	 n += 1 while n != n.to_s.reverse.to_i
	return n
end
puts next_palindrome(111)