#include using namespace std ; #define fast_input_output ios::sync_with_stdio(false); cin.tie(nullptr); typedef long long ll ; typedef long double ld ; typedef pair P ; typedef tuple TP ; #define chmin(a,b) a = min(a,b) #define chmax(a,b) a = max(a,b) #define bit_count(x) __builtin_popcountll(x) #define gcd(a,b) __gcd(a,b) #define lcm(a,b) a / gcd(a,b) * b #define rep(i,n) for(int i = 0 ; i < n ; i++) #define rrep(i,a,b) for(int i = a ; i < b ; i++) #define endl "\n" int n , m ; ll A[101010] ; map mp ; int main(){ fast_input_output cin >> n >> m ; rep(i,n) cin >> A[i] , mp[A[i] % m]++ ; int res = 0 ; set st ; for(auto it : mp){ int a = it.first , c = it.second ; if(st.count(a) == 1 || st.count(m-a) == 1) continue; st.insert(a) ; st.insert(m-a) ; if(a == 0) continue; res += max(mp[m-a],mp[a]) ; } if(mp[0] > 0) res++ ; cout << res << endl ; }