bitops-nsieve-bits.js 889 B

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  1. // The Great Computer Language Shootout
  2. // http://shootout.alioth.debian.org
  3. //
  4. // Contributed by Ian Osgood
  5. function pad(n,width) {
  6. var s = n.toString();
  7. while (s.length < width) s = ' ' + s;
  8. return s;
  9. }
  10. function primes(isPrime, n) {
  11. var i, count = 0, m = 10000<<n, size = m+31>>5;
  12. for (i=0; i<size; i++) isPrime[i] = 0xffffffff;
  13. for (i=2; i<m; i++)
  14. if (isPrime[i>>5] & 1<<(i&31)) {
  15. for (var j=i+i; j<m; j+=i)
  16. isPrime[j>>5] &= ~(1<<(j&31));
  17. count++;
  18. }
  19. }
  20. function sieve() {
  21. for (var i = 4; i <= 4; i++) {
  22. var isPrime = new Array((10000<<i)+31>>5);
  23. primes(isPrime, i);
  24. }
  25. return isPrime;
  26. }
  27. var result = sieve();
  28. var sum = 0;
  29. for (var i = 0; i < result.length; ++i)
  30. sum += result[i];
  31. var expected = -1286749544853;
  32. if (sum != expected)
  33. throw "ERROR: bad result: expected " + expected + " but got " + sum;