add sieve of eratosthenes

Author: dmitrymorozoff

README.md

@@ -23,3 +23,6 @@
 
 ## Хеширование
 1. [Хеш-таблица](https://github.com/dmitrymorozoff/algorithms-in-javascript/blob/master/source/hash-table/hash-table.js) | [Инфо](https://bitsofmind.wordpress.com/2008/07/28/introduction_in_hash_tables/)
+
+## Другое
+1. [Решето Эратосфена](https://github.com/dmitrymorozoff/algorithms-in-javascript/blob/master/source/other/sieve-of-eratosthenes.js) | [Инфо](https://ru.wikipedia.org/wiki/%D0%A0%D0%B5%D1%88%D0%B5%D1%82%D0%BE_%D0%AD%D1%80%D0%B0%D1%82%D0%BE%D1%81%D1%84%D0%B5%D0%BD%D0%B0)

index.html

@@ -20,6 +20,7 @@
     <script src="./source/search/linear-search/linear-search.js" type="module"></script>
     <script src="./source/search/binary-search/binary-search.js" type="module"></script>
     <script src="./source/hash-table/hash-table.js" type="module"></script>
+    <script src="./source/other/sieve-of-eratosthenes.js" type="module"></script>
     <script src="./source/main.js" type="module"></script>
 </body>
 

source/other/sieve-of-eratosthenes.js

@@ -0,0 +1,26 @@
+export default function sieveOfEratosthenes(n) {
+    let primes = [];
+    for (let i = 2; i <= n; i++) {
+        primes[i] = true;
+    }
+    let p = 2;
+    let finished = false;
+    do {
+        for (let i = 2 * p; i <= n; i += p) {
+            primes[i] = false;
+        }
+        for (let i = p; i <= n; i++) {
+            if (primes[i] && i > p) {
+                p = i;
+                break;
+            }
+        }
+    } while (p * p < n);
+    const primesValues = [];
+    for (let i = 2; i <= n; i++) {
+        if (primes[i]) {
+            primesValues.push(i);
+        }
+    }
+    return primesValues;
+}

source/other/sieve-of-eratosthenes.spec.js

@@ -0,0 +1,56 @@
+import sieveOfEratosthenes from "./sieve-of-eratosthenes.js";
+
+describe("sieve-of-eratosthenes", () => {
+    test("should return true if equals", () => {
+        const primes = [
+            2,
+            3,
+            5,
+            7,
+            11,
+            13,
+            17,
+            19,
+            23,
+            29,
+            31,
+            37,
+            41,
+            43,
+            47,
+            53,
+            59,
+            61,
+            67,
+            71,
+            73,
+            79,
+            83,
+            89,
+            97,
+            101,
+            103,
+            107,
+            109,
+            113,
+            127,
+            131,
+            137,
+            139,
+            149,
+            151,
+            157,
+            163,
+            167,
+            173,
+            179,
+            181,
+            191,
+            193,
+            197,
+            199
+        ];
+        const n = 200;
+        expect(sieveOfEratosthenes(n)).toEqual(primes);
+    });
+});