#include #define EPS 1e-9 #define INF 1070000000LL #define MOD 1000000007LL #define fir first #define foreach(it,X) for(auto it=(X).begin();it!=(X).end();it++) #define numa(x,a) for(auto x: a) #define ite iterator #define mp make_pair #define rep(i,n) rep2(i,0,n) #define rep2(i,m,n) for(int i=m;i<(n);i++) #define pb push_back #define pf push_front #define sec second #define sz(x) ((int)(x).size()) #define ALL( c ) (c).begin(), (c).end() #define gcd(a,b) __gcd(a,b) #define mem(x,n) memset(x,n,sizeof(x)) #define endl "\n" using namespace std; template void deploy(std::ostream &os, const TUPLE &tuple){} template void deploy(std::ostream &os, const TUPLE &t){ os << (POS == 0 ? "" : ", ") << get(t); deploy(os, t); } template std::ostream& operator<<(std::ostream &os, std::pair &p){ os << "(" << p.first <<", " << p.second <<")";return os; } template std::ostream& operator<<(std::ostream &os, std::vector &v){ int remain = v.size(); os << "{"; for(auto e: v) os << e << (--remain == 0 ? "}" : ", "); return os; } template std::ostream& operator<<(std::ostream &os, std::set &v){ int remain = v.size(); os << "{"; for(auto e: v) os << e << (--remain == 0 ? "}" : ", "); return os; } template std::ostream& operator<<(std::ostream &os, std::map &mp){ int remain = mp.size(); os << "{"; for(auto e: mp) os << "(" << e.first << " -> " << e.second << ")" << (--remain == 0 ? "}" : ", "); return os; } #define DEBUG1(var0) { std::cerr << (#var0) << "=" << (var0) << endl; } #define DEBUG2(var0, var1) { std::cerr << (#var0) << "=" << (var0) << ", ";DEBUG1(var1); } #define DEBUG3(var0, var1, var2) { std::cerr << (#var0) << "=" << (var0) << ", ";DEBUG2(var1,var2); } #define DEBUG4(var0, var1, var2, var3) { std::cerr << (#var0) << "=" << (var0) << ", ";DEBUG3(var1,var2,var3); } using ll = long long; vector Eratosthenes(int mynum){ vector flag(mynum+1); vector ans; rep2(i,2,mynum+1){ if(!flag[i]){ ans.pb(i); for(int j = 2 * i ; j <= mynum ; j += i){ flag[j] = true; } }else{ ; } } return ans; } int M, N; ll memo[23][10010]; int main() { cin.tie(0); ios_base::sync_with_stdio(0); cin >> M; cin >> N; //int nums[23]; set n2; rep(i,N){ int x; cin >> x; n2.insert(x); } vector nums(sz(n2)+1); int cnt = 1; numa(x,n2){ nums[cnt++] = x; } N = sz(nums) - 1; memo[0][0] = 1; for (int i = 1; i <= N; i++) {//20 for (int j = 0; j <= 10000; j++) {//10000 if (memo[i-1][j] > 0) { for (int k = 0; j + nums[i] * k <= 10000; k++) {//j / nums[i] memo[i][j+nums[i]*k] = max(memo[i][j+nums[i*k]], memo[i-1][j] + k); } } } } auto primes = Eratosthenes(10000); ll ans = 0; numa(p, primes){ int target = M - p; if (target >= 0 && memo[N][target] > 1) { //DEBUG2(target ,memo[N][target] - 1); ans += memo[N][target] - 1; } } ll ret = 0; for (int i = 0; i <= M; i++) { if (memo[N][i] > 1) { ret = max(ret, memo[N][i] - 1); } } cout << ans+ret << endl; return 0; }