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Contest: Task: Related: TaskA TaskC

Score : $400$ points

Problem Statement

Given are integers $N$ and $K$. How many quadruples of integers $(a,b,c,d)$ satisfy both of the following conditions?

  • $1 \leq a,b,c,d \leq N$
  • $a+b-c-d=K$

Constraints

  • $1 \leq N \leq 10^5$
  • $-2(N-1) \leq K \leq 2(N-1)$
  • All numbers in input are integers.

Input

Input is given from standard input in the following format:

$N$ $K$

Output

Print the answer.

Sample Input 1

2 1

Sample Output 1

4

Four quadruples below satisfy the conditions:

  • $(a,b,c,d)=(2,1,1,1)$
  • $(a,b,c,d)=(1,2,1,1)$
  • $(a,b,c,d)=(2,2,2,1)$
  • $(a,b,c,d)=(2,2,1,2)$

Sample Input 2

2525 -425

Sample Output 2

10314607400