Advertisement
Guest User

Untitled

a guest
Feb 26th, 2017
67
0
Never
Not a member of Pastebin yet? Sign Up, it unlocks many cool features!
text 0.73 KB | None | 0 0
  1. #include <bits/stdc++.h>
  2.  
  3. using namespace std;
  4. ifstream fin("sprime.in");
  5. ofstream fout("sprime.out");
  6. int n,i,a[100001],p[100001],m=0,s,nr=0,w;
  7. void Ciurul()
  8. {
  9. int j;
  10. for(i=4; i<=n; i+=2)
  11. a[i]=1;
  12. for(i=3; i*i<=n; i+=2)
  13. if(a[i]==0)
  14. for(j=i*i; j<=n; j=j+2*i)
  15. a[j]=1;
  16. a[1]=1;
  17. m = 0;
  18. for(i=1; i<=n; i++)
  19. if(a[i]==0) p[++m]=i;
  20. }
  21. void Rezolvare()
  22. {
  23. int j;
  24. for(i=1;i<=m;i++)
  25. {
  26. for(j=i;j<=m;j++)
  27. {
  28. w=n-p[i]-p[j];
  29. if(w>1&&a[w]==0&&w>=p[j])
  30. nr++;
  31. }
  32. }
  33. fout<<nr<<"\n";
  34. }
  35. int main()
  36. {
  37. fin>>n;
  38. Ciurul();
  39. Rezolvare();
  40. fout.close();
  41. return 0;
  42. }
Advertisement
Add Comment
Please, Sign In to add comment
Advertisement