#include <bits/stdc++.h>
typedef unsigned long long ll;
#define INF 1000000000
using namespace std;
#define N 100000
int main(void){
    int n,x;
    cin>>n>>x;
    int cnt[N+5]={0};
    vector<int>a(n);
    for(int i=0;i<n;i++){
        cin>>a[i];
        cnt[a[i]]++;
    }
    
    ll ans=0;
    for(int i=0;i<n;i++){
        int d=x-a[i];
        if(0<=d and d<=N){
            ans+=cnt[d];
        }
    }
    cout<<ans<<endl;
}