#include <iostream>
#include <vector>
#include <algorithm>

using namespace std;

#define REP(i,n) for(int i = 0; i < (n); ++i)
#define P(x) cout << (x) << "\n"
#define D(x) cerr << (x) << "\n"
#define fcout cout << fixed << setprecision(18)

using i64=long long int; // 10^18
vector<i64> a;

bool isOK(i64 index, i64 key){
    if(a[index] >= key) return true;
    else return false;
}

i64 binary_search(i64 key) {
    i64 ng = -1;
    i64 ok = (int)a.size();

    while(abs(ok - ng) > 1){
        i64 mid = ng + (ok - ng) / 2;

        if(isOK(mid, key))ok = mid;
        else ng = mid;
    }
    return ok;
}

int main(){
  ios::sync_with_stdio(false);
  cin.tie(0);
  
  int n;cin>>n;
  i64 x;cin>>x;
  REP(i,n){
      i64 in;cin>>in;
      a.push_back(in);
  }

  i64 sum=0;
  sort(a.begin(), a.end());
  for(auto xx:a){
      sum += binary_search(x - xx + 1) - binary_search(x - xx);
  }
  P(sum);
  return 0;
}