prime-table.hpp

/**
 * @brief Prime Table(素数テーブル)
 *
 */
vector<bool> prime_table(int n) {
  vector<bool> prime(n + 1, true);
  if (n >= 0) prime[0] = false;
  if (n >= 1) prime[1] = false;
  for (int i = 2; i * i <= n; i++) {
    if (!prime[i]) continue;
    for (int j = i * i; j <= n; j += i) {
      prime[j] = false;
    }
  }
  return prime;
}