rename and reorganizing (#194)

Maths/SieveOfEratosthenes.js

@@ -0,0 +1,31 @@
+function sieveOfEratosthenes (n) {
+  /*
+     * Calculates prime numbers till a number n
+     * :param n: Number upto which to calculate primes
+     * :return: A boolean list contaning only primes
+     */
+  const primes = new Array(n + 1)
+  primes.fill(true) // set all as true initially
+  primes[0] = primes[1] = false // Handling case for 0 and 1
+  const sqrtn = Math.ceil(Math.sqrt(n))
+  for (let i = 2; i <= sqrtn; i++) {
+    if (primes[i]) {
+      for (let j = 2 * i; j <= n; j += i) {
+        primes[j] = false
+      }
+    }
+  }
+  return primes
+}
+
+function main () {
+  const n = 69 // number till where we wish to find primes
+  const primes = sieveOfEratosthenes(n)
+  for (let i = 2; i <= n; i++) {
+    if (primes[i]) {
+      console.log(i)
+    }
+  }
+}
+
+main()