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Saleh127

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Apr 21st, 2020
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  1. #include <bits/stdc++.h>
  2. using namespace std;
  3. #define M 1000000
  4. bool marked[M];
  5. bool isPrime(int n)
  6. {
  7. if (n < 2) return false;
  8. if (n == 2) return true;
  9. if (n % 2 == 0) return false;
  10. return marked[n] == false;
  11. }
  12. void sieve(int n)
  13. {
  14. for (int i = 3; i * i <= n; i += 2)
  15. {
  16. if (marked[i] == false)
  17. {
  18. // i is a prime
  19. for (int j = i * i; j <= n; j += 2*i)
  20. {
  21. marked[j] = true;
  22. }
  23. }
  24. }
  25. }
  26. int main()
  27. {
  28. int a,b,c;
  29. cin>>a;
  30. if(isPrime(a)== true ) cout<<"Prime\n";
  31. else cout<<"Not Prime\n";
  32. return 0;
  33. }
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