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.
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