#include "bits/stdc++.h"
using namespace std;
#define FOR(i,j,k) for(int (i)=(j);(i)<(int)(k);++(i))
#define rep(i,j) FOR(i,0,j)
#define each(x,y) for(auto &(x):(y))
#define mp make_pair
#define all(x) (x).begin(),(x).end()
#define debug(x) cout<<#x<<": "<<(x)<<endl
#define smax(x,y) (x)=max((x),(y))
#define smin(x,y) (x)=min((x),(y))
#define MEM(x,y) memset((x),(y),sizeof (x))
#define sz(x) (int)(x).size()
typedef long long ll;
typedef pair<int, int> pii;
typedef vector<int> vi;
typedef vector<ll> vll;

vector<int> sieve(int n){
    vector<bool> f(n+1);
    for(int i=3; i<=n; i+=2) f[i] = 1;
    for(int i=3; i<=sqrt(n); i+=2) if(f[i]) for(int j=i*3; j<=n; j+=i) f[j] = 0;
    vector<int> res{2};
    for(int i=3; i<=n; i+=2) if(f[i]) res.push_back(i);
    return res;
}


int main(){
    int M, N;
    while(cin >> M >> N){
        vi C(N);
        rep(i, N)cin >> C[i];
        sort(all(C));
        C.erase(unique(all(C)), C.end());
        N = sz(C);
        vector<int> dp(M + 1, -1);
        dp[M] = 0;
        each(c, C){
            int cnt = M / c;
            for(int k = 1; cnt; k<<=1){
                int m = min(k, cnt);
                for(int j = M; j >= 0; --j){
                    if(j + m*c <= M && dp[j+m*c]!=-1){
                        smax(dp[j], dp[j + m*c]+m);
                    }
                }
                cnt -= m;
            }
        }
        ll ans = 0;
        auto ps = sieve(M);
        each(p, ps)if(dp[p] != -1)ans += dp[p];
        while(M - C[0] >= 0){
            ans++;
            M -= C[0];
        }
        cout << ans << endl;
    }
}