const input =   require('fs').readFileSync('/dev/stdin', 'utf8').slice(0,-1);
const [N, X, ...a] = input.split(/\s/);
const Counter = arr => [...new Set(arr)]
  .map(v1 => ([v1, arr.filter(v2 => v2 === v1).length]))
  .reduce((obj, [k, v]) => ({
    ...obj,
  [k]: v
  }), {});

const cnt = Counter(a);
console.log(
  a
  .map(v => cnt[X - v])
  .reduce((a, b) => a + b)
)