#include <bits/stdc++.h>
using namespace std;
using ll = long long;
#define rep(i, s, e) for (int i = (int)s; i < (int)e; ++i)
#define all(a) (a).begin(), (a).end()

int main() {
    cin.tie(nullptr);
    
    ll N, M;
    cin >> N >> M;
    vector<ll> A(N);
    rep(i, 0, N) cin >> A[i];
    rep(i, 0, N) A[i] %= M;
    
    set<ll> s;
    map<ll, int> m;
    rep(i, 0, N) {
        s.insert(A[i]);
        m[A[i]]++;
    }
    
    ll ans = 0;
    set<ll> seen;
    for (ll i : s) {
        if (seen.count(i)) continue;
        
        if (i == 0) {
            ans++;
            continue;
        }
        
        if (i * 2 == M) {
            ans++;
            continue;
        }
        
        seen.insert(i);
        
        if (s.count(M - i)) {
            ans += max(m[i], m[M - i]);
            seen.insert(M - i);
        } else {
            ans += m[i];
        }
    }
    
    cout << ans << '\n';
}