#line 1 "c.cpp" #include #include #define rep(i,n) for (int i = 0; i < int(n); ++i) #define repp(i,n,m) for (int i = m; i < int(n); ++i) #define reb(i,n) for (int i = int(n)-1; i >= 0; --i) #define all(v) v.begin(),v.end() using namespace std; using namespace atcoder; using ll = long long; using ull = unsigned long long; using ld = long double; using P = pair; using PL = pair; using pdd = pair; using pil = pair; using pli = pair; templateistream &operator>>(istream &is,vector &v){for(auto &e:v)is>>e;return is;} templatebool range(T a,T b,T x){return (a<=x&&xbool rrange(T a,T b,T c,T d,T x,T y){return (range(a,c,x)&&range(b,d,y));} template T rev(const T& str_or_vec){T res = str_or_vec; reverse(res.begin(),res.end()); return res; } templatebool chmin(T &a,const T &b){if(a>b){a=b;return true;}return false;} templatebool chmax(T &a,const T &b){if(avoid uniq(vector &v){sort(v.begin(),v.end());v.erase(unique(v.begin(),v.end()),v.end());} templatevoid print(pair a); templatevoid print(vector v); templatevoid print(vector> v); void print(){ putchar(' '); } void print(bool a){ printf("%d", a); } void print(int a){ printf("%d", a); } void print(long a){ printf("%ld", a); } void print(long long a){ printf("%lld", a); } void print(char a){ printf("%c", a); } void print(char a[]){ printf("%s", a); } void print(const char a[]){ printf("%s", a); } void print(long double a){ printf("%.15Lf", a); } void print(const string& a){ for(auto&& i : a) print(i); } void print(unsigned int a){ printf("%u", a); } void print(unsigned long long a) { printf("%llu", a); } template void print(const T& a){ cout << a; } int out(){ putchar('\n'); return 0; } template int out(const T& t){ print(t); putchar('\n'); return 0; } template int out(const Head& head, const Tail&... tail){ print(head); putchar(' '); out(tail...); return 0; } templatevoid print(pair a){print(a.first);print(),print(a.second);} templatevoid print(vector v){for(auto ite=v.begin();ite!=v.end();){print(*ite);if(++ite!=v.end())print();}} templatevoid print(vector> v){for(auto ite=v.begin();ite!=v.end();){print(*ite);if(++ite!=v.end())out();}} void yes(){out("Yes");} void no (){out("No");} void yn (bool t){if(t)yes();else no();} void fast_io(){cin.tie(0); ios::sync_with_stdio(0); cout< dx = {0,1,0,-1,1,1,-1,-1}; const vector dy = {1,0,-1,0,1,-1,-1,1}; const string ALP = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"; const string alp = "abcdefghijklmnopqrstuvwxyz"; const string NUM = "0123456789"; } // namespace noya2 using namespace noya2; using mint = modint998244353; //using mint = modint1000000007; //using mint = modint; void out(mint a){out(a.val());} void out(vector a){vector b(a.size()); rep(i,a.size()) b[i] = a[i].val(); out(b);} void out(vector> a){for (auto v : a) out(v);} istream &operator>>(istream &is,vector &v){for(auto &e:v){ll _x;is>>_x;e=_x;}return is;} #line 2 "math.hpp" #line 6 "math.hpp" namespace noya2{ using namespace std; using ll = long long; template T sqrt_safe(T x){ // floor(sqrt(x)) assert(x >= T(0)); if (x <= T(1)) return x; T tmp = (T)(sqrtl((long double)(x))) + T(2); while (tmp--){ if (tmp * tmp <= x) break; } return tmp; } ll mod_safe(ll a, ll m){ // m >= 1, 0 <= mod_safe(a,m) < m, mod_safe(a,m) = a (mod m) ll res = a % m; if (res < 0) res += m; return res; } ll modpow(ll x, ll n, ll mod){ x = mod_safe(x,mod); if (n == 0) return 1; ll res = modpow(x,n/2,mod); res = (res * res) % mod; if (n % 2 == 1) res = (res * x) % mod; return res; } ll naive_gcd(ll a, ll b){ return b ? naive_gcd(b, a % b) : a; } // gcd(N >= 0, 0) = N, especialy gcd(0, 0) = 0 ll gcd_safe(ll a, ll b){ return naive_gcd(abs(a),abs(b)); } ll lcm_safe(ll a, ll b){ return a / gcd_safe(a,b) * b; } void ext_gcd1_plus(ll a, ll b, ll &x, ll &y){ // gcd(a,b) = 1, a >= 0, b >= 0, ax + by = 1 if (b == 0){ // a = 1 x = 1, y = 0; return ; } ext_gcd1_plus(b, a%b, y, x); x = mod_safe(x,b); y = (1 - a * x) / b; } void ext_gcd1_minus(ll a, ll b, ll &x, ll &y){ // gcd(a,b) = 1, a >= 0, b >= 0, ax - by = 1 if (b == 0){ // a = 1 x = 1, y = 0; return ; } ext_gcd1_plus(b, a%b, y, x); x = mod_safe(x,b); y = (a * x - 1) / b; } pair ext_gcd(ll a, ll b, ll c){ // ax + by = c, |a|,|b|,|c| < 1e9, x <= max(|B|,|C|), y <= max(|A|,|C|) if (a < 0) return ext_gcd(-a,-b,-c); if (c < 0){ pair res = ext_gcd(a,b,-c); res.first = -res.first, res.second = -res.second; return res; } if (c == 0) return pair(0,0); if (a == 0 && b == 0) return pair(0,0); // answer not exist ll g = gcd_safe(a,b); if (c % g != 0) return pair(0,0); // answer not exist a /= g, b /= g, c /= g; ll x, y; if (b == 0) return pair(c,0); if (b > 0) ext_gcd1_plus(a,b,x,y); else ext_gcd1_minus(a,-b,x,y); x = mod_safe(x*c,abs(b)); y = (c - a * x) / b; return pair(x,y); } template T ceil_safe(T p, T q); template T floor_safe(T p, T q){ if (q < T(0)) return floor_safe(-p,-q); if (p >= T(0)) return p / q; return -ceil_safe(-p,q); } template T ceil_safe(T p, T q){ if (q < T(0)) return ceil_safe(-p,-q); if (p >= T(0)) return (p + q - 1) / q; return -floor_safe(-p,q); } struct Eratosthenes{ static vector table; Eratosthenes (int Nmax = -1) {init(Nmax);} static void init(int Nmax){ if (!table.empty()) return ; table.resize(Nmax+1,0); table[0] = 1, table[1] = 1; for (int p = 2; p <= Nmax; p++){ if (table[p] != 0) continue; for (int j = p; j <= Nmax; j += p){ table[j] = p; } } } }; vectorEratosthenes::table = vector(0); void build_eratosthenes(const int Nmax){Eratosthenes::init(Nmax);} vector> fast_prime_factorization(int N){ int pre = -1, cnt = 0; vector> res; while(true) { if (N == 1){ if (cnt > 0) res.emplace_back(pre,cnt); break; } int div = Eratosthenes::table[N]; if (pre != div){ if (cnt > 0) res.emplace_back(pre,cnt); pre = div, cnt = 1; } else cnt++; N /= div; } return res; } vector fast_divisor_enumeration(int N){ auto pes = fast_prime_factorization(N); vector res = {1}; for (auto pe : pes){ vector nres; for (auto x : res){ for (int _t = 0; _t <= pe.second; _t++){ nres.emplace_back(x); x *= pe.first; } } swap(res,nres); } return res; } bool fast_is_prime(int N){ if (N <= 1) return false; return Eratosthenes::table[N] == N; } vector mobius(int N){ vector res(N+1,0); res[1] = 1; for (int p = 2; p <= N; p++){ if (fast_is_prime(p)){ for (int i = N/p; i > 0; i--){ res[i*p] = -res[i]; } } } return res; }; vector> prime_factorization(ll N){ vector> res; ll iN = N; for (ll d = 2; d * d <= N; d++){ if (iN % d != 0) continue; if (iN == 1) break; int ie = 0; while (iN % d == 0) iN /= d, ie++; res.emplace_back(d,ie); } if (iN != 1) res.emplace_back(iN,1); return res; } vector divisor_enumeration(ll N){ vector res; for (ll d = 1; d * d <= N; d++){ if (N % d != 0) continue; res.emplace_back(d); if (d * d != N) res.emplace_back(N/d); } return res; } bool is_prime(ll N){ if (N <= 1) return false; if (N <= 3) return true; if (N % 2 == 0) return false; for (ll d = 3; d * d <= N; d += 2){ if (N % d == 0) return false; } return true; } }// namespace noya2 #line 78 "c.cpp" void solve(){ int n; cin >> n; vector a(n); cin >> a; const int mx = 100000; build_eratosthenes(mx); vector dp(mx+1,-INF); dp[1] = 0; int ans = 1; rep(i,n){ int ma = 0; for (int d : fast_divisor_enumeration(a[i])){ chmax(ma,dp[d]+1); } chmax(ans,ma); chmax(dp[a[i]],ma); } out(ans); } int main(){ fast_io(); int t = 1; //cin >> t; while(t--) solve(); }