#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define repr(i, n) for (int i = (int)(n); i >= 0; i--)
#define all(v) v.begin(), v.end()
#define mod1 1000000007
#define mod2 998244353
typedef long long ll;

int main(){
    ll N, M;
    cin >> N >> M;
    vector<ll> A(N);
    rep(i,N) cin >> A[i];
    map<ll,ll> mp;
    for (ll i = 0; i < N; i++){
        mp[A[i] % M]++;
    }
    ll ans = 0;
    for (auto itr = mp.begin(); itr != mp.end(); itr++){
        if (itr->first == 0){
            ans += min(1LL, itr->second);
        }
        else{
            if (M % 2 == 0 && itr->first == M / 2){
                ans += min(1LL, itr->second);
            }
            else{
                if (mp[M - itr->first] == 0){
                    ans += (itr->second);
                }
                else{
                    if (itr->first > M / 2) continue;
                    else ans += max(itr->second, mp[M - (itr->first)]);
                }
                
            }
        }
        //cout << ans << endl;
    }
    cout << ans << endl;
}