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: Accepted)

# すぬけ君は，数直線上の位置 x に住んでいます． 
# また，位置 a,b にはそれぞれ出前を行っている店 A,B が存在します．
# すぬけ君は，店 A,B のうち，より近いほうから出前をとることにしました． 
# どちらの店がすぬけ君の住んでいる位置により近いかを求めてください．
# ただし，数直線上の 2 点 s,t の間の距離は |s−t| で表されます．

input = gets.chomp.split
x = input[0].to_i
a = input[1].to_i
b = input[2].to_i

puts (x - a).abs < (x - b).abs ? "A" : "B"