Problem:
How many ways?

Write a program which identifies the number of combinations of three integers which satisfy the following conditions:

You should select three distinct integers from 1 to n.

A total sum of the three integers is x.

For example, there are two combinations for n = 5 and x = 9.

1 + 3 + 5 = 9

2 + 3 + 4 = 9

Input

The input consists of multiple datasets. For each dataset, two integers n and x are given in a line.

The input ends with two zeros for n and x respectively. Your program should not process for these terminal symbols.

Constraints

3 ≤ n ≤ 100

0 ≤ x ≤ 300

Output

For each dataset, print the number of combinations in a line.

Sample Input

5 9
0 0

Sample Output

2

Note

      解説

Solution in Python3 (judge verdict: Accepted)

a=[]
w=""
while(w!="0 0"):
    w=input()
    a.append(w)
a.pop()
for st in a:
    s=st.split()
    n=int(s[0])
    x=int(s[1])
    count=0
    for a in range(1,x//3+1):
        for b in range(a+1,(x-a)//2+1):
            if (x-a-b)<=n and b<(x-a-b):
                count+=1
    print("{0}".format(count))