#include <iostream>
#include <vector>
#include <string>
#include <algorithm>
#include <cmath>
#include <tuple>
#include <bitset>

#define rep(i,n) for(i=0; i<n; ++i)
#define in(a) cin >> a
#define out(a,b) cout << a << b
using namespace std;
using lint = long long;

int main(void){
    lint i, j;
    lint n, m;
    in(n);
    in(m);
    vector<lint> rem(m,0);
    rep(i,n){
        lint num;
        in(num);
        rem[num%m]++;
    }
    lint cnt=0;
    if(rem[0]!=0)   cnt++;
    for(i=1; i<((m-1)/2)+1; ++i){
        lint max;
        rem[i]>rem[m-i]? max=rem[i]: max=rem[m-i];
        cnt+=max;
    }
    if((m-1)%2==1)  cnt+=rem[(m-1)/2+1];
    if(cnt<1)   cnt=1;
    out(cnt,endl);

    return 0;
}