Initial data commit

Task/Miller-Rabin-primality-test/JavaScript/miller-rabin-primality-test.js

@@ -0,0 +1,24 @@
+function probablyPrime(n) {
+  if (n === 2 || n === 3) return true
+  if (n % 2 === 0 || n < 2) return false
+
+  // Write (n - 1) as 2^s * d
+  var s = 0,
+    d = n - 1
+  while ((d & 1) == 0) {
+    d >>= 1
+    ++s
+  }
+
+  let base = 2
+  var x = Math.pow(base, d) % n
+
+  if (x == 1 || x == n - 1) return true
+
+  for (var i = 1; i <= s; i++) {
+    x = (x * x) % n
+
+    if (x === n - 1) return true
+  }
+  return false
+}