#define _USE_MATH_DEFINES
#include <bits/stdc++.h>
using namespace std;
#define FOR(i,m,n) for(int i=(m);i<(n);++i)
#define REP(i,n) FOR(i,0,n)
#define ALL(v) (v).begin(),(v).end()
using ll = long long;
constexpr int INF = 0x3f3f3f3f;
constexpr long long LINF = 0x3f3f3f3f3f3f3f3fLL;
constexpr double EPS = 1e-8;
constexpr int MOD = 1000000007;
// constexpr int MOD = 998244353;
constexpr int DY4[]{1, 0, -1, 0}, DX4[]{0, -1, 0, 1};
constexpr int DY8[]{1, 1, 0, -1, -1, -1, 0, 1};
constexpr int DX8[]{0, -1, -1, -1, 0, 1, 1, 1};
template <typename T, typename U>
inline bool chmax(T& a, U b) { return a < b ? (a = b, true) : false; }
template <typename T, typename U>
inline bool chmin(T& a, U b) { return a > b ? (a = b, true) : false; }
struct IOSetup {
  IOSetup() {
    std::cin.tie(nullptr);
    std::ios_base::sync_with_stdio(false);
    std::cout << fixed << setprecision(20);
  }
} iosetup;

int main() {
  int n; ll m; cin >> n >> m;
  map<ll, int> a;
  while (n--) {
    ll a_i; cin >> a_i;
    ++a[a_i % m];
  }
  int ans = 0;
  if (a.count(0)) {
    ++ans;
    a.erase(0);
  }
  if (m % 2 == 0 && a.count(m / 2)) {
    ++ans;
    a.erase(m / 2);
  }
  while (!a.empty()) {
    const auto [md, num] = *a.begin();
    a.erase(a.begin());
    if (a.count(m - md)) {
      ans += max(num, a[m - md]);
      a.erase(m - md);
    } else {
      ans += num;
    }
  }
  cout << ans << '\n';
  return 0;
}