#include <bits/stdc++.h>

#ifdef DEBUG
#include <Mylib/Debug/debug.cpp>
#else
#define dump(...) ((void)0)
#endif

template <typename T, typename U>
bool chmin(T &a, const U &b){
  return (a > b ? a = b, true : false);
}

template <typename T, typename U>
bool chmax(T &a, const U &b){
  return (a < b ? a = b, true : false);
}

template <typename T, size_t N, typename U>
void fill_array(T (&a)[N], const U &v){
  std::fill((U*)a, (U*)(a + N), v);
}

template <typename T, size_t N, size_t I = N>
auto make_vector(const std::array<int, N> &a, T value = T()){
  static_assert(I >= 1);
  static_assert(N >= 1);
  if constexpr (I == 1){
    return std::vector<T>(a[N - I], value);
  }else{
    return std::vector(a[N - I], make_vector<T, N, I - 1>(a, value));
  }
}

template <typename T>
std::ostream& operator<<(std::ostream &s, const std::vector<T> &a){
  for(auto it = a.begin(); it != a.end(); ++it){
    if(it != a.begin()) s << " ";
    s << *it;
  }
  return s;
}

template <typename T>
std::istream& operator>>(std::istream &s, std::vector<T> &a){
  for(auto &x : a) s >> x;
  return s;
}


namespace haar_lib {}

namespace solver {
  using namespace haar_lib;

  constexpr int m1000000007 = 1000000007;
  constexpr int m998244353 = 998244353;

  void init(){
    std::cin.tie(0);
    std::ios::sync_with_stdio(false);
    std::cout << std::fixed << std::setprecision(12);
    std::cerr << std::fixed << std::setprecision(12);
    std::cin.exceptions(std::ios_base::failbit);
  }

  void solve(){
    int N; std::cin >> N;
    std::vector<int> A(N); std::cin >> A;
    for(auto &x : A){
      x %= 10;
    }

    std::vector<int> count(10);
    for(auto &x : A) count[x] += 1;

    std::vector<int64_t> dp(10, INT_MIN);
    dp[0] = 0;

    for(int i = 0; i < 10; ++i){

      std::vector<int64_t> temp(10, INT_MIN);
      temp[0] = 0;
      for(int j = 1, k = 0; j <= count[i]; ++j){
        (k += i) %= 10;
        chmax(temp[k], j);
      }

      //dump(temp);

      std::vector<int64_t> dp2(10, INT_MIN);

      for(int j = 0; j < 10; ++j){
        for(int k = 0; k < 10; ++k){
          chmax(dp2[(j + k) % 10], dp[j] + temp[k]);
        }
      }

      //dump(dp, dp2, temp);

      std::swap(dp, dp2);
    }

    std::cout << dp[0] << "\n";
  }
}

int main(){
  solver::init();
  while(true){
    try{
      solver::solve();
    }catch(const std::istream::failure &e){
      break;
    }
  }
  return 0;
}