結果
問題 |
No.2075 GCD Subsequence
|
ユーザー |
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提出日時 | 2022-09-16 22:13:04 |
言語 | C++17 (gcc 13.3.0 + boost 1.87.0) |
結果 |
AC
|
実行時間 | 308 ms / 4,000 ms |
コード長 | 2,955 bytes |
コンパイル時間 | 2,079 ms |
コンパイル使用メモリ | 222,760 KB |
最終ジャッジ日時 | 2025-02-07 09:47:07 |
ジャッジサーバーID (参考情報) |
judge3 / judge2 |
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ファイルパターン | 結果 |
---|---|
sample | AC * 3 |
other | AC * 28 |
コンパイルメッセージ
main.cpp: In function ‘std::pair<std::vector<int>, std::vector<int> > {anonymous}::primes_lpf(int)’: main.cpp:34:48: warning: result of ‘2^4’ is 6; did you mean ‘1 << 4’ (16)? [-Wxor-used-as-pow] 34 | for (; x <= n5; x += add_next, add_next ^= 2 ^ 4) { | ^ | - | 1 << main.cpp:34:46: note: you can silence this warning by using a hexadecimal constant (0x2 rather than 2) 34 | for (; x <= n5; x += add_next, add_next ^= 2 ^ 4) { | ^ | 0x2 main.cpp:48:47: warning: result of ‘2^4’ is 6; did you mean ‘1 << 4’ (16)? [-Wxor-used-as-pow] 48 | for (; x <= n; x += add_next, add_next ^= 2 ^ 4) { | ^ | - | 1 << main.cpp:48:45: note: you can silence this warning by using a hexadecimal constant (0x2 rather than 2) 48 | for (; x <= n; x += add_next, add_next ^= 2 ^ 4) { | ^ | 0x2
ソースコード
#include<bits/stdc++.h> namespace { #pragma GCC diagnostic push #pragma GCC diagnostic ignored "-Wunused-function" #include<atcoder/all> #pragma GCC diagnostic pop using namespace std; using namespace atcoder; #define rep(i,n) for(int i = 0; i < (int)(n); i++) #define rrep(i,n) for(int i = (int)(n) - 1; i >= 0; i--) #define all(x) begin(x), end(x) #define rall(x) rbegin(x), rend(x) template<class T> bool chmax(T& a, const T& b) { if (a < b) { a = b; return true; } else return false; } template<class T> bool chmin(T& a, const T& b) { if (b < a) { a = b; return true; } else return false; } using ll = long long; using P = pair<int,int>; using VI = vector<int>; using VVI = vector<VI>; using VL = vector<ll>; using VVL = vector<VL>; using mint = modint998244353; pair<vector<int>, vector<int>> primes_lpf(const int n) { vector<int> primes; primes.reserve(n / 10); vector<int> lpf(n + 1); for (int i = 2; i <= n; i += 2) lpf[i] = 2; for (int i = 3; i <= n; i += 6) lpf[i] = 3; if (2 <= n) primes.push_back(2); if (3 <= n) primes.push_back(3); // 5 * x <= n, x <= floor(n / 5) const int n5 = n / 5; int x = 5; char add_next = 2; for (; x <= n5; x += add_next, add_next ^= 2 ^ 4) { int px = lpf[x]; if (px == 0) { lpf[x] = px = x; primes.push_back(x); } for (int i = 2;; ++i) { int q = primes[i]; int y = q * x; if (y > n) break; lpf[y] = q; if (q == px) break; } } for (; x <= n; x += add_next, add_next ^= 2 ^ 4) { if (lpf[x] == 0) { lpf[x] = x; primes.push_back(x); } } return {move(primes), move(lpf)}; } constexpr int PSIZE = 1000000; auto [primes, lpf] = primes_lpf(PSIZE); VI factorize(int x) { int ps[10], cs[10]; int sz = 0; while (x != 1) { int p = lpf[x], c = 0; do {x /= p; c++;} while (x % p == 0); ps[sz] = p; cs[sz] = c; sz++; } VI fs(ps, ps + sz); // for (int i = 0; i < sz; i++) fs.emplace_back(ps[i], cs[i]); return fs; } vector<signed char> build_mu_table(const int n) { assert(n < (int)lpf.size()); vector<signed char> res(n + 1); for(int p: primes) { if (p > n) break; res[p] = 1; } for(int x = 2; x <= n; x++) { if (!res[x]) continue; int px = lpf[x]; for(int q: primes) { if (q == px) break; int y = q * x; if (y > n) break; res[y] = -res[x]; } } return res; } auto mu = build_mu_table(1000000); } int main() { ios::sync_with_stdio(false); cin.tie(0); int n; cin >> n; vector<mint> dp(1000000); mint ans; rep(_, n) { int x; cin >> x; auto ps = factorize(x); int sz = ps.size(); mint tot; rep(s, 1 << sz) if (s) { int t = 1; rep(k, sz) if (s >> k & 1) t *= ps[k]; tot += dp[t] * mu[t]; } tot++; ans += tot; rep(s, 1 << sz) if (s) { int t = 1; rep(k, sz) if (s >> k & 1) t *= ps[k]; dp[t] += tot; } } cout << ans.val() << '\n'; }