#include <bits/stdc++.h>
using namespace std;
#define int              long long int
#define double           long double
#define print(a)         for(auto x : a) cout << x << " "; cout << endl


const int M = 1000000007;
const int N = 3e5+9;
const int INF = 2e9+1;
const int LINF = 2000000000000000001;

inline int power(int a, int b, int mod=M) {
    int x = 1;
    a %= mod;
    while (b) {
        if (b & 1) x = (x * a) % mod; 
        a = (a * a) % mod;
        b >>= 1;
    }
    return x;
}


//_ ***************************** START Below *******************************




vector<int> a;


int consistency(int n, int k){
	
	int ans = 0;
	int s = 0, e = n-1;
	
	while(s<e){
		if(a[s] + a[e] > k){
			e--;
		}
		else if(a[s] + a[e] < k){
			s++;
		}
		else{
			int x = a[s];
			int ct1 = 0;
			while(s<=e && a[s] == x){
				ct1++;
				s++;
			}
			
			int y = a[e];
			int ct2 = 0;
			while(e>=s && a[e] == y){
				ct2++;
				e--;
			}
			
			if(x == y) ans += ct1*(ct1-1)/2;
			else ans += ct1*ct2;
		}
	}
	return ans;
}






















int practice(int n){


    return 0;
}





void solve() {
    
    int n, k;
    cin>> n >> k;
    
    a.resize(n);
    for(int i=0; i<n; i++) cin >> a[i];
    
    cout << consistency(n, k) << endl;


}





int32_t main() {
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);

    int t = 1;
    // cin >> t;
    while (t--) {
        solve();
    }

    return 0;
}