import java.io.*; import java.util.*; /** * @author baito */ @SuppressWarnings("unchecked") public class Main { static StringBuilder sb = new StringBuilder(); static FastScanner sc = new FastScanner(System.in); static int INF = 123456789; static int MINF = -123456789; static long LINF = 123456789123456789L; static long MLINF = -123456789123456789L; static long MOD = 1000000007; static int[] y4 = {0, 1, 0, -1}; static int[] x4 = {1, 0, -1, 0}; static int[] y8 = {0, 1, 0, -1, -1, 1, 1, -1}; static int[] x8 = {1, 0, -1, 0, 1, -1, 1, -1}; static long[] Fa;//factorial static boolean[] isPrime; static int[] primes; static char[][] map; static int N, M, K; static int[] A; public static void main(String[] args) { //longを忘れるなオーバーフローするぞ N = sc.nextInt(); int X = sc.nextInt(); A = sc.nextIntArray(N); Arrays.sort(A); long res = 0; for (int i = 0; i < N; i++) { long kosu = (upperBound(A, X - A[i]) - lowerBound(A, X - A[i])); res += kosu; } System.out.println(res); } public static long sqrt(long v) { long res = (long) Math.sqrt(v); while (res * res > v) res--; return res; } public static int upper0(int a) { if (a < 0) return 0; return a; } public static long upper0(long a) { if (a < 0) return 0; return a; } public static Integer[] toIntegerArray(int[] ar) { Integer[] res = new Integer[ar.length]; for (int i = 0; i < ar.length; i++) { res[i] = ar[i]; } return res; } //k個の次の組み合わせをビットで返す 大きさに上限はない 110110 -> 111001 public static int nextCombSizeK(int comb, int k) { int x = comb & -comb; //最下位の1 int y = comb + x; //連続した下の1を繰り上がらせる return ((comb & ~y) / x >> 1) | y; } public static int keta(long num) { int res = 0; while (num > 0) { num /= 10; res++; } return res; } public static long getHashKey(int a, int b) { return (long) a << 32 | b; } public static boolean isOutofIndex(int x, int y) { if (x < 0 || y < 0) return true; if (map[0].length <= x || map.length <= y) return true; return false; } public static void setPrimes() { int n = 100001; isPrime = new boolean[n]; List prs = new ArrayList<>(); Arrays.fill(isPrime, true); isPrime[0] = isPrime[1] = false; for (int i = 2; i * i <= n; i++) { if (!isPrime[i]) continue; prs.add(i); for (int j = i * 2; j < n; j += i) { isPrime[j] = false; } } primes = new int[prs.size()]; for (int i = 0; i < prs.size(); i++) primes[i] = prs.get(i); } public static void revSort(int[] a) { Arrays.sort(a); reverse(a); } public static void revSort(long[] a) { Arrays.sort(a); reverse(a); } public static int[][] copy(int[][] ar) { int[][] nr = new int[ar.length][ar[0].length]; for (int i = 0; i < ar.length; i++) for (int j = 0; j < ar[0].length; j++) nr[i][j] = ar[i][j]; return nr; } /** *

指定した値以上の先頭のインデクスを返す

*

配列要素が0のときは、0が返る。

* * @returnint : 探索した値以上で、先頭になるインデクス * 値が無ければ、挿入できる最小のインデックス */ public static int lowerBound(final int[] arr, final int value) { int low = 0; int high = arr.length; int mid; while (low < high) { mid = ((high - low) >>> 1) + low; //(low + high) / 2 (オーバーフロー対策) if (arr[mid] < value) { low = mid + 1; } else { high = mid; } } return low; } /** *

指定した値より大きい先頭のインデクスを返す

*

配列要素が0のときは、0が返る。

* * @returnint : 探索した値より上で、先頭になるインデクス * 値が無ければ、挿入できる最小のインデックス */ public static int upperBound(final int[] arr, final int value) { int low = 0; int high = arr.length; int mid; while (low < high) { mid = ((high - low) >>> 1) + low; //(low + high) / 2 (オーバーフロー対策) if (arr[mid] <= value) { low = mid + 1; } else { high = mid; } } return low; } /** *

指定した値以上の先頭のインデクスを返す

*

配列要素が0のときは、0が返る。

* * @returnint : 探索した値以上で、先頭になるインデクス * 値がなければ挿入できる最小のインデックス */ public static long lowerBound(final long[] arr, final long value) { int low = 0; int high = arr.length; int mid; while (low < high) { mid = ((high - low) >>> 1) + low; //(low + high) / 2 (オーバーフロー対策) if (arr[mid] < value) { low = mid + 1; } else { high = mid; } } return low; } /** *

指定した値より大きい先頭のインデクスを返す

*

配列要素が0のときは、0が返る。

* * @returnint : 探索した値より上で、先頭になるインデクス * 値がなければ挿入できる最小のインデックス */ public static long upperBound(final long[] arr, final long value) { int low = 0; int high = arr.length; int mid; while (low < high) { mid = ((high - low) >>> 1) + low; //(low + high) / 2 (オーバーフロー対策) if (arr[mid] <= value) { low = mid + 1; } else { high = mid; } } return low; } //次の順列に書き換える、最大値ならfalseを返す public static boolean nextPermutation(int A[]) { int len = A.length; int pos = len - 2; for (; pos >= 0; pos--) { if (A[pos] < A[pos + 1]) break; } if (pos == -1) return false; //posより大きい最小の数を二分探索 int ok = pos + 1; int ng = len; while (Math.abs(ng - ok) > 1) { int mid = (ok + ng) / 2; if (A[mid] > A[pos]) ok = mid; else ng = mid; } swap(A, pos, ok); reverse(A, pos + 1, len - 1); return true; } //次の順列に書き換える、最小値ならfalseを返す public static boolean prevPermutation(int A[]) { int len = A.length; int pos = len - 2; for (; pos >= 0; pos--) { if (A[pos] > A[pos + 1]) break; } if (pos == -1) return false; //posより小さい最大の数を二分探索 int ok = pos + 1; int ng = len; while (Math.abs(ng - ok) > 1) { int mid = (ok + ng) / 2; if (A[mid] < A[pos]) ok = mid; else ng = mid; } swap(A, pos, ok); reverse(A, pos + 1, len - 1); return true; } //↓nCrをmod計算するために必要。 ***factorial(N)を呼ぶ必要がある*** static long ncr(int n, int r) { if (n < r) return 0; else if (r == 0) return 1; factorial(n); return Fa[n] / (Fa[n - r] * Fa[r]); } static long ncr2(int a, int b) { if (b == 0) return 1; else if (a < b) return 0; long res = 1; for (int i = 0; i < b; i++) { res *= a - i; res /= i + 1; } return res; } static long ncrdp(int n, int r) { if (n < r) return 0; long[][] dp = new long[n + 1][r + 1]; for (int ni = 0; ni < n + 1; ni++) { dp[ni][0] = dp[ni][ni] = 1; for (int ri = 1; ri < ni; ri++) { dp[ni][ri] = dp[ni - 1][ri - 1] + dp[ni - 1][ri]; } } return dp[n][r]; } static long modNcr(int n, int r) { if (n < r) return 0; long result = Fa[n]; result = result * modInv(Fa[n - r]) % MOD; result = result * modInv(Fa[r]) % MOD; return result; } public static long modSum(long... lar) { long res = 0; for (long l : lar) res = (res + l % MOD) % MOD; if (res < 0) res += MOD; res %= MOD; return res; } public static long modDiff(long a, long b) { long res = a % MOD - b % MOD; if (res < 0) res += MOD; res %= MOD; return res; } public static long modMul(long... lar) { long res = 1; for (long l : lar) res = (res * l % MOD) % MOD; if (res < 0) res += MOD; res %= MOD; return res; } public static long modDiv(long a, long b) { long x = a % MOD; long y = b % MOD; long res = (x * modInv(y)) % MOD; return res; } static long modInv(long n) { return modPow(n, MOD - 2); } static void factorial(int n) { Fa = new long[n + 1]; Fa[0] = Fa[1] = 1; for (int i = 2; i <= n; i++) { Fa[i] = (Fa[i - 1] * i) % MOD; } } static long modPow(long x, long n) { long res = 1L; while (n > 0) { if ((n & 1) == 1) { res = res * x % MOD; } x = x * x % MOD; n >>= 1; } return res; } //↑nCrをmod計算するために必要 static int gcd(int n, int r) { return r == 0 ? n : gcd(r, n % r); } static long gcd(long n, long r) { return r == 0 ? n : gcd(r, n % r); } static void swap(T[] x, int i, int j) { T t = x[i]; x[i] = x[j]; x[j] = t; } static void swap(int[] x, int i, int j) { int t = x[i]; x[i] = x[j]; x[j] = t; } public static void reverse(int[] x) { int l = 0; int r = x.length - 1; while (l < r) { int temp = x[l]; x[l] = x[r]; x[r] = temp; l++; r--; } } public static void reverse(long[] x) { int l = 0; int r = x.length - 1; while (l < r) { long temp = x[l]; x[l] = x[r]; x[r] = temp; l++; r--; } } public static void reverse(char[] x) { int l = 0; int r = x.length - 1; while (l < r) { char temp = x[l]; x[l] = x[r]; x[r] = temp; l++; r--; } } public static void reverse(int[] x, int s, int e) { int l = s; int r = e; while (l < r) { int temp = x[l]; x[l] = x[r]; x[r] = temp; l++; r--; } } static int length(int a) { int cou = 0; while (a != 0) { a /= 10; cou++; } return cou; } static int length(long a) { int cou = 0; while (a != 0) { a /= 10; cou++; } return cou; } static int cou(boolean[] a) { int res = 0; for (boolean b : a) { if (b) res++; } return res; } static int cou(String s, char c) { int res = 0; for (char ci : s.toCharArray()) { if (ci == c) res++; } return res; } static int countC2(char[][] a, char c) { int co = 0; for (int i = 0; i < a.length; i++) for (int j = 0; j < a[0].length; j++) if (a[i][j] == c) co++; return co; } static int countI(int[] a, int key) { int co = 0; for (int i = 0; i < a.length; i++) if (a[i] == key) co++; return co; } static int countI(int[][] a, int key) { int co = 0; for (int i = 0; i < a.length; i++) for (int j = 0; j < a[0].length; j++) if (a[i][j] == key) co++; return co; } static void fill(int[][] a, int v) { for (int i = 0; i < a.length; i++) for (int j = 0; j < a[0].length; j++) a[i][j] = v; } static void fill(long[][] a, long v) { for (int i = 0; i < a.length; i++) for (int j = 0; j < a[0].length; j++) a[i][j] = v; } static void fill(int[][][] a, int v) { for (int i = 0; i < a.length; i++) for (int j = 0; j < a[0].length; j++) for (int k = 0; k < a[0][0].length; k++) a[i][j][k] = v; } static int max(int... a) { int res = Integer.MIN_VALUE; for (int i : a) { res = Math.max(res, i); } return res; } static long min(long... a) { long res = Long.MAX_VALUE; for (long i : a) { res = Math.min(res, i); } return res; } static int max(int[][] ar) { int res = Integer.MIN_VALUE; for (int i[] : ar) res = Math.max(res, max(i)); return res; } static int min(int... a) { int res = Integer.MAX_VALUE; for (int i : a) { res = Math.min(res, i); } return res; } static int min(int[][] ar) { int res = Integer.MAX_VALUE; for (int i[] : ar) res = Math.min(res, min(i)); return res; } static int sum(int[] a) { int cou = 0; for (int i : a) cou += i; return cou; } static int abs(int a) { return Math.abs(a); } static class FastScanner { private BufferedReader reader = null; private StringTokenizer tokenizer = null; public FastScanner(InputStream in) { reader = new BufferedReader(new InputStreamReader(in)); tokenizer = null; } public String next() { if (tokenizer == null || !tokenizer.hasMoreTokens()) { try { tokenizer = new StringTokenizer(reader.readLine()); } catch (IOException e) { throw new RuntimeException(e); } } return tokenizer.nextToken(); } /*public String nextChar(){ return (char)next()[0]; }*/ public String nextLine() { if (tokenizer == null || !tokenizer.hasMoreTokens()) { try { return reader.readLine(); } catch (IOException e) { throw new RuntimeException(e); } } return tokenizer.nextToken("\n"); } public long nextLong() { return Long.parseLong(next()); } public int nextInt() { return Integer.parseInt(next()); } public double nextDouble() { return Double.parseDouble(next()); } public int[] nextIntArray(int n) { int[] a = new int[n]; for (int i = 0; i < n; i++) { a[i] = nextInt(); } return a; } public int[] nextIntArrayOneIndex(int n) { int[] a = new int[n + 1]; for (int i = 1; i < n + 1; i++) { a[i] = nextInt(); } return a; } public int[] nextIntArrayDec(int n) { int[] a = new int[n]; for (int i = 0; i < n; i++) { a[i] = nextInt() - 1; } return a; } public int[][] nextIntArray2(int h, int w) { int[][] a = new int[h][w]; for (int hi = 0; hi < h; hi++) { for (int wi = 0; wi < w; wi++) { a[hi][wi] = nextInt(); } } return a; } public int[][] nextIntArray2Dec(int h, int w) { int[][] a = new int[h][w]; for (int hi = 0; hi < h; hi++) { for (int wi = 0; wi < w; wi++) { a[hi][wi] = nextInt() - 1; } } return a; } //複数の配列を受け取る public void nextIntArrays2ar(int[] a, int[] b) { for (int i = 0; i < a.length; i++) { a[i] = sc.nextInt(); b[i] = sc.nextInt(); } } public void nextIntArrays2arDec(int[] a, int[] b) { for (int i = 0; i < a.length; i++) { a[i] = sc.nextInt() - 1; b[i] = sc.nextInt() - 1; } } //複数の配列を受け取る public void nextIntArrays3ar(int[] a, int[] b, int[] c) { for (int i = 0; i < a.length; i++) { a[i] = sc.nextInt(); b[i] = sc.nextInt(); c[i] = sc.nextInt(); } } //複数の配列を受け取る public void nextIntArrays3arDecLeft2(int[] a, int[] b, int[] c) { for (int i = 0; i < a.length; i++) { a[i] = sc.nextInt() - 1; b[i] = sc.nextInt() - 1; c[i] = sc.nextInt(); } } public Integer[] nextIntegerArray(int n) { Integer[] a = new Integer[n]; for (int i = 0; i < n; i++) { a[i] = nextInt(); } return a; } public char[] nextCharArray(int n) { char[] a = next().toCharArray(); return a; } public char[][] nextCharArray2(int h, int w) { char[][] a = new char[h][w]; for (int i = 0; i < h; i++) { a[i] = next().toCharArray(); } return a; } //スペースが入っている場合 public char[][] nextCharArray2s(int h, int w) { char[][] a = new char[h][w]; for (int i = 0; i < h; i++) { a[i] = nextLine().replace(" ", "").toCharArray(); } return a; } public char[][] nextWrapCharArray2(int h, int w, char c) { char[][] a = new char[h + 2][w + 2]; //char c = '*'; int i; for (i = 0; i < w + 2; i++) a[0][i] = c; for (i = 1; i < h + 1; i++) { a[i] = (c + next() + c).toCharArray(); } for (i = 0; i < w + 2; i++) a[h + 1][i] = c; return a; } //スペースが入ってる時用 public char[][] nextWrapCharArray2s(int h, int w, char c) { char[][] a = new char[h + 2][w + 2]; //char c = '*'; int i; for (i = 0; i < w + 2; i++) a[0][i] = c; for (i = 1; i < h + 1; i++) { a[i] = (c + nextLine().replace(" ", "") + c).toCharArray(); } for (i = 0; i < w + 2; i++) a[h + 1][i] = c; return a; } public long[] nextLongArray(int n) { long[] a = new long[n]; for (int i = 0; i < n; i++) { a[i] = nextLong(); } return a; } public long[][] nextLongArray2(int h, int w) { long[][] a = new long[h][w]; for (int hi = 0; hi < h; hi++) { for (int wi = 0; wi < w; wi++) { a[hi][wi] = nextLong(); } } return a; } } }