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  1. #include <iostream>
  2. #include <cmath>
  3.  
  4. const int MAX = 20;
  5.  
  6. bool arrStorePrimes[MAX] = { 0 };
  7.  
  8. void ShowPrimes(int min, int max);
  9.  
  10. bool isPrime(int n)
  11. {
  12.     if(n == 1)
  13. 		return false;
  14.  
  15. 	if(n < MAX && arrStorePrimes[n] != 0)
  16. 	{
  17. 		return true;
  18. 	}
  19.  
  20.         int sq = sqrt(n);
  21.  
  22. 	for(int i = 3; i <= sq; i += 2)
  23. 	{
  24. 		if(n % i == 0)
  25. 			return false;
  26. 	}
  27.  
  28. 	if(n < MAX)
  29. 		arrStorePrimes[n] = 1;
  30.  
  31. 	return true;
  32. }
  33. int main()
  34. {
  35. 	using std::cin;
  36. 	int num;
  37. 	cin >> num;
  38. 	int min, max;
  39.  
  40. 	while(num)
  41. 	{
  42. 		cin >> min;
  43. 		cin >> max;
  44. 		ShowPrimes(min, max);
  45. 		num--;
  46. 	}
  47. 	return 0;
  48. }
  49.  
  50. void ShowPrimes(int min, int max)
  51. {
  52. 	if( min % 2 == 0 )
  53. 		++min;
  54. 	for(int i = min; i <= max; i += 2)
  55. 	{
  56. 		if(isPrime(i))
  57. 			std::cout << i << std::endl;
  58. 	}
  59. }
Success #stdin #stdout 0s 2688KB
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https://ideone.com/9YJPHu
language:
C++ 4.3.2 (gcc-4.3.2)
created:
10 years ago
visibility:
public

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