definition of the function which determines the power of 2 which dire…

…ctly follows a given number

src/algorithms/math/power-of-two-greater-than-number/__test__/powerOfTwoGreaterThanNumber.test.js

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+import powerOfTwoGreaterThanNumber from '../powerOfTwoGreaterThanNumber';
+
+describe('powerOfTwoGreaterThanNumber', () => {
+  it('should calculate the power of two greater than the given number', () => {
+    expect(powerOfTwoGreaterThanNumber(-1)).toBe(-1);
+    expect(powerOfTwoGreaterThanNumber(0)).toBe(-1);
+    expect(powerOfTwoGreaterThanNumber(1)).toBe(2);
+    expect(powerOfTwoGreaterThanNumber(2)).toBe(4);
+    expect(powerOfTwoGreaterThanNumber(3)).toBe(4);
+    expect(powerOfTwoGreaterThanNumber(14)).toBe(16);
+    expect(powerOfTwoGreaterThanNumber(27)).toBe(32);
+    expect(powerOfTwoGreaterThanNumber(63)).toBe(64);
+    expect(powerOfTwoGreaterThanNumber(500)).toBe(512);
+    expect(powerOfTwoGreaterThanNumber(1000)).toBe(1024);
+    expect(powerOfTwoGreaterThanNumber(2000)).toBe(2048);
+    expect(powerOfTwoGreaterThanNumber(4097)).toBe(8192);
+  });
+});

src/algorithms/math/power-of-two-greater-than-number/powerOfTwoGreaterThanNumber.js

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+/**
+ * @param {number} number
+ * @return {number}
+ */
+export default function powerOfTwoGreaterThanNumber(number) {
+  // if number is negative or equal to 0, we return -1
+  if (number <= 0) {
+    return -1;
+  }
+
+  const power = Math.floor(Math.log(number) / Math.log(2)) + 1;
+
+  return 2 ** power;
+}