import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.util.HashSet;
import java.util.Set;

public class Main {
	public static void main(String[] args) throws Exception {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		String[] sa = br.readLine().split(" ");
		int n = Integer.parseInt(sa[0]);
		int m = Integer.parseInt(sa[1]);
		sa = br.readLine().split(" ");
		int[] a = new int[n];
		Set<Integer> set = new HashSet<>();
		for (int i = 0; i < n; i++) {
			a[i] = Integer.parseInt(sa[i]);
			set.add(a[i]);
		}
		br.close();

		if (m % 2 == 1) {
			System.out.println(0);
			return;
		}

		long ans = 0;
		int m2 = m / 2;
		for (int i = 0; i < n; i++) {
			int v = a[i] + m2;
			v %= m;
			if (v == 0) {
				v = m;
			}
			if (set.contains(v)) {
				ans += n - 2;
			}
		}
		System.out.println(ans / 2);
	}
}