#include #include #define rep(i,b) for(int i=0;i=0;i--) #define rep1(i,b) for(int i=1;i using mpq = priority_queue, greater>; template bool chmax(T &a, const T &b) { if (a bool chmin(T &a, const T &b) { if (b ll sumv(const vector&a){ll res(0);for(auto&&x:a)res+=x;return res;} bool yn(bool a) { if(a) {cout << "Yes" << endl; return 1;} else {cout << "No" << endl; return 0;}} #define dame { cout << "No" << endl; return 0;} #define dame1 { cout << -1 << endl; return 0;} #define test(x) cout << "test" << x << endl; #define deb(x,y) cout << x << " " << y << endl; #define deb3(x,y,z) cout << x << " " << y << " " << z << endl; #define deb4(x,y,z,x2) cout << x << " " << y << " " << z << " " << x2 << endl; #define out cout << ans << endl; #define outv fore(yans , ans) cout << yans << "\n"; #define show(x) cerr<<#x<<" = "<; using pil = pair; using pli = pair; using pii = pair; using tp = tuple; using vi = vector; using vl = vector; using vs = vector; using vb = vector; using vpii = vector; using vpli = vector; using vpll = vector; using vpil = vector; using vvi = vector>; using vvl = vector>; using vvs = vector>; using vvb = vector>; using vvpii = vector>; using vvpli = vector>; using vvpll = vector; using vvpil = vector; using mint = modint998244353; using vm = vector; using vvm = vector>; vector dx={1,0,-1,0,1,1,-1,-1},dy={0,1,0,-1,1,-1,1,-1}; ll gcd(ll a, ll b) { return a?gcd(b%a,a):b;} ll lcm(ll a, ll b) { return a/gcd(a,b)*b;} const double eps = 1e-10; const ll LINF = 1001002003004005006ll; const int INF = 1001001001; struct math_lib{ vvl div,mul; void div_init(int n){ div.resize(n+1); mul.resize(n+1); for(ll i = 1;i <= n;i++){ for(ll j = i;j <= n;j+=i){ div[j].pb(i); mul[i].pb(j); } } return; } vl divisor(ll x){ vl res; for(ll i=1;i*i<=x;i++){ if (x%i != 0) continue; res.pb(i); if (i*i != x) res.pb(x/i); } sort(rng(res)); return res; } ll sqrt(ll x) { ll l = 0, r = ll(2e9)+1; while (l+1= LLONG_MAX/a) break; tmp *= a; ret++; } ret--; return ret; } ll base(ll x,int a){ ll ans=0,y; for (ll i=0;x>0;i++){ y = x/a; ans += (x - y*a)*pow(10,i); x = y; } return ans; } string baseS(ll x,int a){ string ans; ll y; for (ll i=0;x>0;i++){ y = x/a; ans += '0' + (x - y*a); x = y; } reverse(rng(ans)); return ans; } } math; // .div.mul : div[i]、mul[i]はそれぞれiの約数、倍数を格納している。 // .div_init(n) : div,mulを初期化。引数はnまで。n < 1e6 ~ 1e7。 // .divisor(x) : xの約数列挙。xは64bit整数。 // .sqrt(x) : floor(sqrt(x))。xは64bit整数。誤差は発生しない。 // .logx(x , a) : floor(loga(x))。xは64bit整数。誤差は発生しない。 // .base(x , a) : x(10進数)をa進数表記に。1 <= a <= 10。戻り値はll型。 // .baseS(x , a) : x(10進数)をa進数表記に。1 <= a <= 10。戻り値はstring型。 int main(){ int n,m; cin>>n>>m; math.div_init(n+1); vl open(n+1); rep(i,m){ ll a; cin>>a; open[a] = 1; } vl now(n); ll ans = 0; rrep(i,n+1){ if (i == 0) break; if (now[i] == open[i]){ ans++; }else{ fore(y , math.div[i]) now[y] ^= 1; } } out; return 0; }