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 JavaScript (judge verdict: Accepted)

function Main(input) {
let dataset = input.split('\n');
let nx = [];
let n, x
for (let i = 0; i < dataset.length; i++){
nx = dataset[i].split(' ').map(Number);
n = nx[0]
x = nx[1]

let count = 0;
if (n === 0 && x === 0) {
break;
} else {
for (let j = 1; j < n; j++){
for (let k = j + 1; k < n; k++){
for (let l = k + 1; l <= n; l++ ){
if ((l + k + j) === x) {
count++;
} else {

}
}
}
}
console.log(count);
}
}
}

Main(require("fs").readFileSync("/dev/stdin", "utf8"));