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  1. #include "bits/stdc++.h"
  2. using namespace std;
  3.  
  4. #define int int64_t
  5. #define trav(i, a) for(auto& i: a)
  6. #define all(a) a.begin(), a.end()
  7. #define rall(a) a.rbegin(), a.rend()
  8. #define si(a) ((int)(a).size())
  9. #define ins insert
  10. #define pb push_back
  11. #define mp make_pair
  12. #define f first
  13. #define s second
  14.  
  15. const int MOD = 1e9 + 7;
  16. const int INF = 1e18;
  17. const string nl = "\n";
  18.  
  19. struct timer {
  20. 	decltype(chrono::high_resolution_clock::now()) begin;
  21. 	void start() {
  22. 		begin = chrono::high_resolution_clock::now();
  23. 	}
  24. 	void end() {
  25. 		auto end = chrono::high_resolution_clock::now();
  26. 		auto duration = chrono::duration_cast<chrono::milliseconds>(end - begin).count();
  27. 		cerr << duration << "ms elapsed" << endl;
  28. 	}
  29. };
  30.  
  31. const int N = 1e8;
  32.  
  33. vector<bool> isp(N, true);
  34.  
  35. void sieve() {
  36. 	isp[0] = isp[1] = 0;
  37. 	for(int i = 2; i < N; ++i) {
  38. 		if(!isp[i]) {
  39. 			continue;
  40. 		}
  41. 		for(int j = i * i; j < N; j += i) {
  42. 			isp[j] = false;
  43. 		}
  44. 	}
  45. }
  46.  
  47. vector<bool> is_prime(N, true);
  48.  
  49. void sieve1() {
  50. 	is_prime[0] = is_prime[1] = 0;
  51. 	for(int i = 2; i < N; ++i) {
  52. 		for(int j = i * i; j < N; j += i) {
  53. 			is_prime[j] = false;
  54. 		}
  55. 	}
  56. }
  57.  
  58. int32_t main() {
  59. 	ios::sync_with_stdio(0);
  60. 	cin.tie(nullptr);
  61.  
  62. 	timer a;
  63. 	a.start();
  64. 	sieve();
  65. 	a.end();
  66. 	a.start();
  67. 	sieve1();
  68. 	a.end();
  69. }
  70.  
Success #stdin #stdout #stderr 4.7s 27416KB
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https://ideone.com/lo9wqE
language:
C++ (gcc 8.3)
created:
4 years ago
visibility:
secret

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