Score : 200 points

Problem Statement

You are given two integers K and S.
Three variable X, Y and Z takes integer values satisfying 0≤X,Y,Z≤K.
How many different assignments of values to X, Y and Z are there such that X + Y + Z = S?

Constraints

  • 2≤K≤2500
  • 0≤S≤3K
  • K and S are integers.

Input

The input is given from Standard Input in the following format:

K S

Output

Print the number of the triples of X, Y and Z that satisfy the condition.

Sample Input 1

2 2

Sample Output 1

6

There are six triples of X, Y and Z that satisfy the condition:

  • X = 0, Y = 0, Z = 2
  • X = 0, Y = 2, Z = 0
  • X = 2, Y = 0, Z = 0
  • X = 0, Y = 1, Z = 1
  • X = 1, Y = 0, Z = 1
  • X = 1, Y = 1, Z = 0

Sample Input 2

5 15

Sample Output 2

1

The maximum value of X + Y + Z is 15, achieved by one triple of X, Y and Z.