#include using namespace std; #define rep(i,n) for(int i = 0; i < (int)n; i++) #define FOR(n) for(int i = 0; i < (int)n; i++) #define repi(i,a,b) for(int i = (int)a; i < (int)b; i++) #define pb push_back #define m0(x) memset(x,0,sizeof(x)) #define fill(x,y) memset(x,y,sizeof(x)) #define bg begin() #define ed end() #define all(x) x.bg,x.ed //#define mp make_pair #define vi vector #define vvi vector #define vll vector #define vvll vector #define vs vector #define vvs vector #define vc vector #define vvc vector #define pii pair #define pllll pair #define vpii vector> #define vpllll vector> #define vpis vector> #define vplls vector> #define vpsi vector> #define vpsll vector> template void chmax(T &a, const T &b) {a = (a > b? a : b);} template void chmin(T &a, const T &b) {a = (a < b? a : b);} using ll = long long; using ld = long double; using ull = unsigned long long; const ll INF = numeric_limits::max() / 2; const ld pi = 3.1415926535897932384626433832795028; const ll mod = 1e9 + 7; int dx[] = {-1, 0, 1, 0, -1, -1, 1, 1}; int dy[] = {0, -1, 0, 1, -1, 1, -1, 1}; #define int long long void solve() { int n, m; cin >> n >> m; vi a(n); FOR(n) cin >> a[i]; int ans = n; map mp; for(auto e : a) mp[e%m]++; for(auto e : mp) { if(e.first != 0 && e.first*2 != m) { // cout << mp[m-e.first] << endl; ans -= min(mp[e.first], mp[m-e.first]); mp[e.first] = 0; mp[m-e.first] = 0; // cout << mp[m-e.first] << endl; } // cout << e.first << " " << mp[m-e.first] << endl; } if(mp[0]!=0) ans -= mp[0]-1; if(m%2==0&&mp[m/2]!=0) ans -= mp[m/2]-1; // cout << cnt << endl; // assert(cnt%2==0); cout << ans << endl; } signed main() { cin.tie(nullptr); ios::sync_with_stdio(false); solve(); return 0; }