Problem:
Score : 100 points

Problem Statement

Snuke lives at position x on a number line.
On this line, there are two stores A and B, respectively at position a and b, that offer food for delivery.

Snuke decided to get food delivery from the closer of stores A and B.
Find out which store is closer to Snuke's residence.

Here, the distance between two points s and t on a number line is represented by |s-t|.

Constraints

1 \leq x \leq 1000

1 \leq a \leq 1000

1 \leq b \leq 1000

x, a and b are pairwise distinct.

The distances between Snuke's residence and stores A and B are different.

Input

Input is given from Standard Input in the following format:

x a b

Output

If store A is closer, print A; if store B is closer, print B.

Sample Input 1

5 2 7

Sample Output 1

B

The distances between Snuke's residence and stores A and B are 3 and 2, respectively.
Since store B is closer, print B.

Sample Input 2

1 999 1000

Sample Output 2

A

Solution in Ruby (2.3.3) (judge verdict: Runtime Error)

n  = gets.to_i
aa = gets.split.map(&:to_i).sort

a_count = Hash.new(0)
for a in aa
  a_count[a] = a_count[a] + 1
end

selection = []
for a, count in a_count
  if count >= 2
    selection << {"n" => a, "count" => count}
  end
end

if selection.size >= 2
  sorted_selection = selection.sort{|a1, a2| a1["n"] <=> a2["n"] }.reverse
  x = 0
  y = 0
  if sorted_selection[0]["count"] >= 4
    x = sorted_selection[0]["n"]
    y = sorted_selection[0]["n"]
  else
    x = sorted_selection[0]["n"]
    y = sorted_selection[1]["n"]
  end 
  puts x*y
else
  puts 0
end