Sha256: d6733905bfd9072f41edf97fc6950662ac3daf600c957629dbb500b10081032f
Contents?: true
Size: 679 Bytes
Versions: 63
Compression:
Stored size: 679 Bytes
Contents
import ceylon.numeric.float {
sqrt
}
{Integer*} primesUpTo(Integer max) {
// if max < 4, sqrt(max) < 2, so 2..sqrt(max) gives decreasing values.
// Prevent this by just returning the small primes here:
if (max < 4) {
return { 2, 3 }.takeWhile((c) => c <= max);
}
value prime = Array.ofSize(max + 1, true);
prime[0] = false;
prime[1] = false;
for (i in 2 .. (sqrt(max.float).integer)) {
if (!(prime[i] else false)) {
continue;
}
for (multiple in ((i * i) .. max).by(i)) {
prime[multiple] = false;
}
}
return { for (i->p in prime.indexed) if (p) i };
}
Version data entries
63 entries across 63 versions & 1 rubygems