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 Kotlin (1.0.0) (judge verdict: Runtime Error)

fun main(args: Array<String>) {
    val n = readLine()!!

    val count = readLine()!!.split(Regex("\\s+")).map { it.toInt() }
            .groupBy { it }
            .filterValues { it.size >= 2 }
            .mapValues { it.value.size }
            .toList().sortedByDescending { it.first }

    val a = count.getOrElse(0, { i -> 0 to 0 })
    val b = count.getOrElse(1, { i -> 0 to 0 })

    print(a.first * if (a.second >= 4) a.first else b.first)
}