#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/2+m%2); ++i){
        lint elem=max(rem[i],rem[m-i]);
        cnt+=elem;
    }
    if(m%2==0&&rem[m/2]!=0) cnt++;
    if(cnt<1)   cnt=1;
    out(cnt,endl);

    return 0;
}