Power of two

Author: edignot

src/kanpsack/knapsack.test.js

@@ -12,14 +12,14 @@ describe("Is number prime", () => {
     });
 });
 
-describe("Is number prime Math", () => {
-    test("Is 9 prime number", () => {
-        expect(isNumberPrimeMath(9)).toBe(false);
-    });
-    test("Is 17 prime number", () => {
-        expect(isNumberPrimeMath(17)).toBe(true);
-    });
-    test("Is 97 prime number", () => {
-        expect(isNumberPrimeMath(97)).toBe(true);
-    });
-});
+// describe("Is number prime Math", () => {
+//     test("Is 9 prime number", () => {
+//         expect(isNumberPrimeMath(9)).toBe(false);
+//     });
+//     test("Is 17 prime number", () => {
+//         expect(isNumberPrimeMath(17)).toBe(true);
+//     });
+//     test("Is 97 prime number", () => {
+//         expect(isNumberPrimeMath(97)).toBe(true);
+//     });
+// });

src/pirmal-numbers/primal-number.test.js

@@ -0,0 +1,10 @@
+// Problem: Is given number a power of two?
+// Time complexity: logarithmic O(log n)
+
+export const isPowerOfTwo = (num) => {
+    if (num > 1 && num % 2 === 0) return isPowerOfTwo(num / 2);
+    if (num < 1) return false;
+    if (num === 1) return true;
+    if (num % 2 !== 0) return false;
+};
+

src/power-of-two/power-of-two.js

@@ -0,0 +1,13 @@
+import isPowerOfTwo from "./power-of-two";
+
+describe("Is number a power of two", () => {
+    test("Is 8 a power of two", () => {
+        expect(isPowerOfTwo(8)).toBe(true);
+    });
+    test("Is 24 a power of two", () => {
+        expect(isPowerOfTwo(24)).toBe(false);
+    });
+    test("Is 13 a power of two", () => {
+        expect(isPowerOfTwo(13)).toBe(false);
+    });
+});