99pts WA on #10 萌新求调

#include <bits/stdc++.h>

namespace my_std{
	#define one_case int tt = 1; while(tt--)
	#define multi_case int tt; cin>>tt; while(tt--) 
	#define fir(i,a,b) for(int i=(a);i<=(b);++i)
	#define rif(i,a,b) for(int i=(a);i>=(b);++i)
	#define For(i,a,b) for(auto i=(a);i!=(b);++i)
	using LL = long long;
	const int Mod = 1e9+7;	
	template<class T> void qmod(T &x){ x = x<0 ? x+Mod : (x>=Mod ? x-Mod : x); }
	template<class T> T Qmod(T x){ return x<0 ? x+Mod : (x>=Mod ? x-Mod : x); }
	using lf = double;
	const double eps = 1e-10;
	using pii = std::pair<int,int>;
	template<class T1,class T2> auto cp(T1 x,T2 y){
		return std::make_pair(x,y);	
	}
	template<class T1,class T2> std::istream & operator >> (std::istream &in, std::pair<T1,T2> &A){
		in >> A.first >> A.second;
		return in;
	}
	template<class T1,class T2> std::ostream & operator << (std::ostream &ot, std::pair<T1,T2> &A){
		ot << "(" << A.first << "," << A.second <<")";
		return ot;
	}
	using vi = std::vector<int>;
	template<class T> std::istream & operator >> (std::istream &in,std::vector<T> &A){
		size_t Size = A.size();
		For(i,1,Size){
			in >> A[i];
		}
		return in;
	}
	template<class T> std::ostream & operator << (std::ostream &ot,std::vector<T> &A){
		size_t Size = A.size();
		For(i,0,Size){
			ot << A[i]; ot << (i!=Size-1 ? "," : "");
		}
		return ot;
	}
	template<class T> T Abs(T x){ 
		return x>0 ? x : -x; 
	}
	template<class T> T Gcd(T x,T y){
		if(!y) return x;
		return Gcd(y,x%y);
	}
	template<class T> class PQ{
		private:
			std::priority_queue< T,std::vector<T>,std::greater<T> > q1;
			std::priority_queue< T,std::vector<T>,std::greater<T> > q2;
		public:
			void Insert(T x){
				q1.push(x);
			}
			void Delete(T x){
				q2.push(x);
			}
			bool Empty(){
				while(!q1.empty() and !q2.empty() and q1.top()==q2.top()){
					q1.pop();
					q2.pop();
				}		
				return q1.empty();
			}
			T Top(){
				return q1.top();
			}
	};
	void Ios(){ 
		std::ios::sync_with_stdio(false); 
		std::cin.tie(nullptr); 
	}
	void Finish_Coding(){

	}
	template<class ... Args> void Print(Args ... args){
		size_t count = 0;
		( (std::cerr << (count++ ? "," : "") << args), ...);
	}
	#ifdef DEBUG
		#define DDebug(...) \
				cerr << "@" << __func__ << ",#" << __LINE__ << ": ["; \
				Print(#__VA_ARGS__); \
				cerr << "] = {"; \
				Print(__VA_ARGS__); \
				cerr << "}\n";
		#define ddebug(...) \
				"@" << __func__ << ",#" << __LINE__ << ": [" << #__VA_ARGS__ << "] = {" << __VA_ARGS__ << "}"				
	#else
		#define DDebug(...) void(0)
	#endif
}using namespace my_std;

using namespace std;

LL n; int k;

signed main(){
	string __name = "";
	if(__name!=""){
		freopen((__name+".in").c_str(),"r",stdin);
		freopen((__name+".out").c_str(),"w",stdout);
	}
	one_case[&]{
		cin >> n >> k;
		vector<LL> m(k+1);
		cin >> m;
		LL mx = Gcd(n,m[k]);
		DDebug(mx);
		vector<LL> pri;
		auto pre = [&](){
			LL x = mx;
			for(LL d = 2; d*d<=x; ++d){
				if(x%d == 0){
					pri.emplace_back(d);
					while(x%d == 0){
						x/=d;
					}
				}
			} 
			if(x != 1){
				pri.emplace_back(x);
			}
		}; pre();
		DDebug(pri);
		map<LL,bool> vis;
		auto bfs = [&](){
			queue<LL> q;
			fir(i,1,k-1){
				m[i] = Gcd(m[i],mx);
				if( !vis.count(m[i]) ){
					q.push(m[i]);
					vis[ m[i] ] = 1;					
				}
			}
			while(!q.empty()){
				LL u = q.front(); q.pop();
				for(LL d : pri){
					if(LL v = u/d; v*d == u and !vis.count(v) ){
						q.push(v);
						vis[v] = 1;
					}
				}
			}
		}; bfs();
		LL g = mx;
		auto qry = [&](){
			LL x = mx;
			for(LL d = 2; d*d<=x; ++d){
				if(x%d == 0){
					if(x%d == 0){
						if( !vis.count(d) ){
							g = d;
							return;
						}
						if( !vis.count(x/d) ){
							g = x/d;
						}
					}
				}
			}
		}; qry();
		DDebug(g);
		cout << n / g << '\n';
	}();
	Finish_Coding();
}