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 Ruby (judge verdict: Time Limit Exceeded)

while (n,x = gets.split.map(&:to_i)) != [0,0] do
  count = 0
  check_arr = Array.new
  test_arr  = Array.new
  c = 0
  (1..n).each {|i|
    (1..n).each {|j|
      (1..n).each {|k|
        if (i + j + k) == x && i != j && i != k && j != k
          test_arr.clear
          test_arr = i,j,k
          if c == 0 
            check_arr[c] = i,j,k
            c += 1
            # puts "if c == 0の中"
            count += 1
          else
            check_num = 0
            (0..(c - 1)).each {|c|
              # puts "eachの中"
              if check_arr[c].sort == test_arr.sort  
                # puts "breakしまーす"
                break
              end
              # puts "check_numを１増やしまーす"
              check_num += 1
            }
            if check_num == c 
                # print check_arr[c].sort
                # puts
                # print test_arr.sort
                # puts
                check_arr[c] = i,j,k 
                c += 1
                # puts "elseの中"
                count += 1
            end
          end
        end
      }
    }
  }
  puts count
end