just3ws · May 18, 2012 12:35 · just3ws · May 18, 2012
diff --git a/1089.rb b/1089.rb
 # 1) Take any 3 digit number, But the first and third number Cannot be the same.
 # 2) reverse the order and subtract
 # 3) reverse the answer and then add it

 "1234567890"
  .split(//)
  .map {|i| i.to_i }
  .permutation(3)
  .to_a
  .map {|n| [n, n.reverse] }
  .map {|x| [x.first.join, x.last.join].sort.reverse.reduce {|y,z| y.to_i - z.to_i } }
  .map {|x| [x, x.to_s.reverse.to_i].reduce {|y,z| y + z } }
	# 1) Take any 3 digit number, But the first and third number Cannot be the same.
	# 2) reverse the order and subtract
	# 3) reverse the answer and then add it

	"1234567890"
	.split(//)
	.map {\|i\| i.to_i }
	.permutation(3)
	.to_a
	.map {\|n\| [n, n.reverse] }
	.map {\|x\| [x.first.join, x.last.join].sort.reverse.reduce {\|y,z\| y.to_i - z.to_i } }
	.map {\|x\| [x, x.to_s.reverse.to_i].reduce {\|y,z\| y + z } }