#828 Dice and Sum

Statement

Statement language

An $N$ -sided die has the integers from $1$ to $N$ , one on each face. Roll the die independently three times, and let $a_1,a_2,a_3$ be the results in order. The same number may appear more than once.

Count the ordered triples $(a_1,a_2,a_3)$ satisfying the following condition.

|a_1-a_2|+|a_1-a_3|+|a_2-a_3|=K

Input

The input is given in the following format:

$N\ K$

Output

Print the number of ordered triples satisfying the condition.

Constraints

$N,K\in\mathbb{Z}$ .
$1\leq N\leq 10^9$ .
.

Subtasks

#	Score	Constraints
1	20	$N\leq 100$ .
2	80	No additional constraints.

Samples

Sample 1

Input

6 6

Output

54

Sample 2

Input

4 0

Output

4

Sample 3

Input

3 3

Output

0

Sample 4

Input

2 4

Output

0