結果
問題 | No.811 約数の個数の最大化 |
ユーザー |
|
提出日時 | 2020-01-23 17:42:52 |
言語 | C++14 (gcc 13.3.0 + boost 1.87.0) |
結果 |
AC
|
実行時間 | 210 ms / 2,000 ms |
コード長 | 2,538 bytes |
コンパイル時間 | 1,142 ms |
コンパイル使用メモリ | 125,728 KB |
実行使用メモリ | 52,452 KB |
最終ジャッジ日時 | 2024-07-19 11:45:19 |
合計ジャッジ時間 | 4,807 ms |
ジャッジサーバーID (参考情報) |
judge3 / judge5 |
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ファイルパターン | 結果 |
---|---|
sample | AC * 3 |
other | AC * 12 |
ソースコード
#include <cstdio>#include <iostream>#include <string>#include <sstream>#include <stack>#include <algorithm>#include <cmath>#include <queue>#include <map>#include <set>#include <cstdlib>#include <bitset>#include <tuple>#include <assert.h>#include <deque>#include <bitset>#include <iomanip>#include <limits>#include <chrono>#include <random>#include <array>#include <unordered_map>#include <functional>#include <complex>template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; }template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; }const long long MAX = 5100000;const long long INF = 1LL << 60;const long long mod = 1000000007LL;//const long long mod = 998244353LL;using namespace std;typedef unsigned long long ull;typedef long long ll;bool IsPrime[MAX];ll MinFactor[MAX];vector<ll> preprocess(ll n = MAX) {vector<ll> res;for (ll i = 0; i < n; ++i) IsPrime[i] = true, MinFactor[i] = -1;IsPrime[0] = false; IsPrime[1] = false;MinFactor[0] = 0; MinFactor[1] = 1;for (ll i = 2; i < n; ++i) {if (IsPrime[i]) {MinFactor[i] = i;res.push_back(i);for (ll j = i * 2; j < n; j += i) {IsPrime[j] = false;if (MinFactor[j] == -1) MinFactor[j] = i;}}}return res;}vector<pair<ll, ll> > fast_prime_factor(ll n) {vector<pair<ll, ll> > res;while (n != 1) {ll prime = MinFactor[n];ll exp = 0;while (MinFactor[n] == prime) {++exp;n /= prime;}res.push_back(make_pair(prime, exp));}return res;}int main(){/*cin.tie(nullptr);ios::sync_with_stdio(false);*/ll N, K; cin >> N >> K;preprocess();vector<pair<ll, ll>> np = fast_prime_factor(N);ll res = 0;ll cnt = 0;for (ll i = 2; i < N; i++) {ll tmp = 0;map<ll, ll> mp;vector<pair<ll, ll>> vp = fast_prime_factor(i);ll d_cnt = 1;for (auto p : vp) {mp[p.first] = p.second;d_cnt *= (p.second + 1);}for (auto p : np) {if (mp.find(p.first) != mp.end()) tmp += min(mp[p.first], p.second);}if (K <= tmp) {if (cnt < d_cnt) {//cout << i << " " << d_cnt << endl;res = i;cnt = d_cnt;}}}cout << res << endl;return 0;}