#include <iostream>
#include <vector>
#include <algorithm>
#include <deque>
#include <queue>
#include <string>
#include <iomanip>
#include <set>
#include <unordered_set>
#include <map>
#include <unordered_map>
#include <utility>
#include <stack>
#include <random>
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <math.h>
#include <assert.h>
#if __has_include(<atcoder/all>)
#include <atcoder/all>
using namespace atcoder;
#endif
using namespace std;
using ll=long long;
#define read(x) cin>>(x);
#define readll(x) ll (x);cin>>(x);
#define readS(x) string (x);cin>>(x);
#define readvll(x,N) vector<ll> (x)((N));for(int i=0;i<(N);i++){cin>>(x)[i];}
#define rep(i,N) for(ll (i)=0;(i)<(N);(i)++)
#define rep2d(i,j,H,W) for(ll (i)=0;(i)<(H);(i)++)for(ll (j)=0;(j)<(W);j++)
#define is_in(x,y) (0<=(x) && (x)<H && 0<=(y) && (y)<W)
#define yn {cout<<"Yes"<<endl;}else{cout<<"No"<<endl;}
inline ll powll(ll x,ll n){ll r=1;while(n>0){if(n&1){r*=x;};x*=x;n>>=1;};return r;}

int main(){
  ll N,M;
  cin>>N>>M;
  readvll(A,N);
  ll ans=0;
  unordered_map<ll,ll> um;
  unordered_set<ll> us;
  for(ll i=0;i<N;i++){
    A[i]%=M;
    um[A[i]]++;
    us.insert(A[i]);
    if(A[i]){
      us.insert(M-A[i]);
    }
  }
  vector<ll> B;
  B.reserve(2*N);
  for(ll i:us){
    if(2*i<=M){
      B.push_back(i);
    }
  }
  //sort(B.begin(),B.end());
  for(ll i:B){
    if(i==0){
      ans++;
    }else if(2*i==M){
      ans++;
    }else{
      ans+=max(um[i],um[M-i]);
    }
  }
  cout<<ans<<endl;
}

/*
2 4 3 0


*/