#include <iostream>
#include <vector>
#include <algorithm>
#include <iterator>
#include <unordered_map>
#include <limits>

inline int get_how_many(const std::vector<int>& W,std::unordered_map<int,int>& how_many,int L){

  if(how_many.end() == how_many.find(L)){
    how_many[L] = std::numeric_limits<int>::max();
    for(auto w : W){
      if(L - w >= 0){
	how_many[L] = std::min(how_many[L],get_how_many(W,how_many,L-w)+1);
      }
    }
  }
  
  return how_many[L];
}

int main(){
  int L,N;
  std::vector<int> W{};
  std::unordered_map<int,int> how_many{};
  
  std::cin >> L >> N;
  how_many.reserve(L+1);
  W.reserve(N);

  std::copy_n(std::istream_iterator<int>(std::cin),N,std::back_inserter(W));
  
  how_many[0] = 0;
  std::cout << get_how_many(W,how_many,L) << std::endl;
  
  return 0;
}