Array.prototype.indexOf = function (num) {
  let left = 0;
  let right = this.length - 1;
  for (;;) {
    if (right < left) return -1;
    const mid = (right - left) / 2 + left | 0;
    if (this[mid] === num && (mid == 0 || this[mid - 1] !== this[mid])) return mid
    if (num <= this[mid]) right = mid - 1;
    else left = mid + 1;
  }
};

Array.prototype.lastIndexOf = function (num) {
  let left = 0;
  let right = this.length - 1;
  for (;;) {
    if (right < left) return -1;
    const mid = (right - left) / 2 + left | 0;
    if (this[mid] === num && (mid == this.length - 1 || this[mid + 1] !== this[mid])) return mid
    if (num < this[mid]) right = mid - 1;
    else left = mid + 1;
  }
};


//const input = require('fs').readFileSync('/dev/stdin', 'utf8').slice(0, -1);
input = `4 5
1 2 0 6
`.slice(0, -1)
let [N, X, ...a] = input.split(/\s/);
a = a
  .map(v => +v)
  .sort((a, b) => a - b);

let sum = 0;
for (const v of a) {
  const index = a.indexOf(X - v);
  sum += index >= 0 ? a.lastIndexOf(X - v) - index + 1 : 0;
}
console.log(sum);