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 C (GCC 5.4.1) (judge verdict: Accepted)

#include <stdio.h>
#include <stdlib.h>
#define MIN 1
#define MAX 1000

int main()
{
    int x, a, b;

    scanf("%d %d %d", &x, &a, &b);

    if ((x >= MIN && x <= MAX) && (a >= MIN && a<= MAX) && (b >= MIN && b <= MAX)) {
        if (abs(x - a) < abs(x - b)) {
            printf("A\n");
        }
        if (abs(x - a) > abs(x - b)) {
            printf("B\n");
        }
    } else {
        return 1;
    }
    return 0;
}