maths.ts/lib/arithmetic/sieve.js

Math utilities library for TypeScript, JavaScript and Node.js

"use strict";
/**
 * @author Hector J. Vasquez <ipi.vasquez@gmail.com>
 *
 * @licence
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
Object.defineProperty(exports, "__esModule", { value: true });
const std_ts_1 = require("std.ts");
/**
 * Default PRIMES's max prime number.
 */
const LIMIT = 1100401;
/**
 * Emulates the PRIMES of Eratosthenes algorithm for finding all prime
 * numbers up to a given limit.
 * @param max The last number this algorithm will reach.
 * @return An array with all prime numbers from 0 to max.
 */
function sieveOfEratosthenes(max = LIMIT) {
    const bs = new std_ts_1.BitSet(max);
    const maxPrimeSqrt = Math.round(Math.sqrt(max));
    const primes = [];
    for (let i = 2; i <= maxPrimeSqrt; i++) {
        if (!bs.get(i)) {
            primes.push(i);
            for (let j = 0; j < max; j += i) {
                bs.set(j, true);
            }
        }
    }
    for (let i = maxPrimeSqrt + ((maxPrimeSqrt & 1) ? 2 : 1); i < max; i += 2) {
        if (!bs.get(i)) {
            primes.push(i);
        }
    }
    return primes;
}
exports.sieveOfEratosthenes = sieveOfEratosthenes;