cf update

Author: coderxiang

Codeforces/Div II/278B_170.rb

@@ -0,0 +1,25 @@
+n = gets.to_i;
+a = (0..n-1).inject([]) {|acc, y| 
+  s = gets.chomp 
+  b = (0..s.length-1).inject([]){ |ai, x|
+    (x..s.length-1).inject(ai){ |aj, y|
+      aj << s[x..y]
+    }
+  }
+  acc + b
+}.sort{ |x, y|  
+  if x.size < y.size 
+    -1
+  elsif x.size > y.size
+    1
+  else
+    if x <= y then -1 else 1 end
+  end
+}.uniq
+ans="a"
+a.each{|x| 
+  break if x != ans
+  ans.succ!
+}
+puts ans
+