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chore: Merge pull request #759 from Aayushi-Mittal/powerOf2

Add code for checking whether given number is a power of 2 or not

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	`1`	`+/*`
	`2`	`+ author: @Aayushi-Mittal`
	`3`	`+`
	`4`	`+ This script will check whether the given`
	`5`	`+ number is a power of two or not.`
	`6`	`+`
	`7`	`+ A number will be a power of two if only one bit is set and rest are unset.`
	`8`	`+ This is true for all the cases except 01 because (2^0 = 1) which is not a power of 2.`
	`9`	`+ For eg: 10 (2^1 = 2), 100 (2^2 = 4), 10000 (2^4 = 16)`
	`10`	`+`
	`11`	`+ Reference Link: https://www.hackerearth.com/practice/notes/round-a-number-to-the-next-power-of-2/`
	`12`	`+`
	`13`	`+ If we will subtract 1 from a number that is a power of 2 we will get it's 1's complement.`
	`14`	`+ And we know that 1's complement is just opp. of that number.`
	`15`	`+ So, (n & (n-1)) will be 0.`
	`16`	`+`
	`17`	`+ For eg: (1000 & (1000-1))`
	`18`	`+ 1 0 0 0 // Original Number (8)`
	`19`	`+ 0 1 1 1 // After Subtracting 1 (8-1 = 7)`
	`20`	`+ _______`
	`21`	`+ 0 0 0 0 // will become 0`
	`22`	`+`
	`23`	`+*/`
	`24`	`+`
	`25`	`+export const IsPowerOfTwo = (n) => {`
	`26`	`+ if (n != 0 && (n & (n - 1)) == 0) return true`
	`27`	`+ else return false`
	`28`	`+}`

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	`1`	`+import {IsPowerOfTwo} from '../IsPowerOfTwo'`
	`2`	`+`
	`3`	`+test('Check if 0 is a power of 2 or not:', () => {`
	`4`	`+ const res = IsPowerOfTwo(0)`
	`5`	`+ expect(res).toBe(false)`
	`6`	`+})`
	`7`	`+`
	`8`	`+test('Check if 0 is a power of 2 or not:', () => {`
	`9`	`+ const res = IsPowerOfTwo(1)`
	`10`	`+ expect(res).toBe(false)`
	`11`	`+})`
	`12`	`+`
	`13`	`+test('Check if 4 is a power of 2 or not:', () => {`
	`14`	`+ const res = IsPowerOfTwo(4)`
	`15`	`+ expect(res).toBe(true)`
	`16`	`+})`
	`17`	`+`
	`18`	`+test('Check if 1024 is a power of 2 or not:', () => {`
	`19`	`+ const res = IsPowerOfTwo(1024)`
	`20`	`+ expect(res).toBe(true)`
	`21`	`+})`
	`22`	`+`
	`23`	`+test('Check if 1025 is a power of 2 or not:', () => {`
	`24`	`+ const res = IsPowerOfTwo(1025)`
	`25`	`+ expect(res).toBe(false)`
	`26`	`+})`

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`10`	`10`
`11`	`11`	`## Bit-Manipulation`
`12`	`12`	`* [BinaryCountSetBits](https://github.com/TheAlgorithms/Javascript/blob/master/Bit-Manipulation/BinaryCountSetBits.js)`
	`13`	`+ * [IsPowerOfTwo](https://github.com/TheAlgorithms/Javascript/blob/master/Bit-Manipulation/IsPowerOfTwo.js)`
`13`	`14`	`* [SetBit](https://github.com/TheAlgorithms/Javascript/blob/master/Bit-Manipulation/SetBit.js)`
`14`	`15`
`15`	`16`	`## Cache`

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