Problem:
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.

Solution in Perl (v5.18.2) (judge verdict: Time Limit Exceeded)

#! usr/bin/perl

use strict;
use warnings;


chomp(my $line = <STDIN>);
my ($K,$S) = split ' ',$line;
my $count = 0;

foreach my $x (0..$K) {
    foreach my $y (0 .. $K) {
        foreach my $z (0..$K){
            if ($x + $y + $z == $S) {
                ++$count;
            }
        }
    }
}

print "$count\n";