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  1. /* package whatever; // don't place package name! */
  2.  
  3. import java.util.*;
  4. import java.lang.*;
  5. import java.io.*;
  6.  
  7. /* Name of the class has to be "Main" only if the class is public. */
  8. class Ideone
  9. {
  10. 	public static void main (String[] args) throws java.lang.Exception
  11. 	{
  12. 		// your code goes here
  13. 		int N = 5_000_000;
  14. 		List<Integer> twins = twinPrimes(N);
  15. 		boolean[] flag = new boolean[N+1];
  16. 		for (int i = 0; i < twins.size(); i++) {
  17. 			int a = twins.get(i);
  18. 			for (int j = i; j < twins.size(); j++) {
  19. 				int b = twins.get(j);
  20. 				int s = a + b;
  21. 				if (s < flag.length) flag[s] = true;
  22. 			}
  23. 		}
  24. 		for (int i = 6; i < flag.length; i += 2) {
  25. 			if (!flag[i]) System.out.print(", " + i);
  26. 		}
  27. 	}
  28.  
  29. 	static List<Integer> twinPrimes(int N) {
  30. 		boolean[] flag = new boolean[N+1];
  31. 		for (int i = 3; i < flag.length; i += 2) {
  32. 			if (flag[i]) continue;
  33. 			for (int j = i+i+i; j < flag.length; j += i+i) {
  34. 				flag[j] = true;
  35. 			}
  36. 		}
  37. 		List<Integer> ret = new ArrayList<>();
  38. 		for (int i = 3; i < flag.length; i += 2) {
  39. 			if (flag[i]) continue;
  40. 			if (i>3&&!flag[i-2]) ret.add(i);
  41. 			else if (i+2<flag.length&&!flag[i+2]) ret.add(i);
  42. 		}
  43. 		return ret;
  44. 	}
  45. }
Success #stdin #stdout 3.23s 2184192KB
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stdin
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Standard input is empty
stdout
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, 94, 96, 98, 400, 402, 404, 514, 516, 518, 784, 786, 788, 904, 906, 908, 1114, 1116, 1118, 1144, 1146, 1148, 1264, 1266, 1268, 1354, 1356, 1358, 3244, 3246, 3248, 4204, 4206, 4208
https://ideone.com/KUvKKi
language:
Java (HotSpot 12)
created:
5 years ago
visibility:
public

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