Problem7068--ABC051 —— B - Sum of Three Integers

7068: ABC051 —— B - Sum of Three Integers

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Time Limit : 1.000 sec  Memory Limit : 256 MiB

Description

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 $X + Y + Z = S$?

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.

Constraints

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

Sample 1 Input

2 2

Sample 1 Output

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 2 Input

5 15

Sample 2 Output

1
The maximum value of $X + Y + Z$ is $15$, achieved by one triple of $X, Y$ and $Z$.

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