mathtools/internal/lib/sieve/common.go

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/*
Copyright © 2025 filifa
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
package sieve
func updateMultiples(sieve []uint, p uint, n uint) {
for q := p; ; q *= p {
// sieve[a*b] = sieve[a] * sieve[b] if gcd(a,b) = 1
for i := 2 * q; i < n; i += q {
if i%(p*q) != 0 {
sieve[i] *= sieve[q]
}
}
if p*q >= n {
break
}
}
}