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merge: Add new IsPalindrome implementation (TheAlgorithms#1046)

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	`1`	`+/**`
	`2`	`+ *@function isPalindromeIterative`
	`3`	`+ *@description isPalindromeIterative function checks whether the provided input is palindrome or not`
	`4`	`+ *@param {String \| Number} x - The input to check`
	`5`	`+ *@return {boolean} - Input is palindrome or not`
	`6`	`+ *@see [Palindrome](https://en.wikipedia.org/wiki/Palindrome)`
	`7`	`+ */`
	`8`	`+`
	`9`	`+/*`
	`10`	`+ * Big-O Analysis`
	`11`	`+ * Time Complexity`
	`12`	`+ - O(N) on average and worst case scenario as input is traversed in linear fashion`
	`13`	`+ - O(N) on best case scenario, even when input has length of 1, because toString() method takes O(N)`
	`14`	`+ * Space Complexity`
	`15`	`+ - O(1)`
	`16`	`+*/`
	`17`	`+`
	`18`	`+exportfunctionisPalindromeIterative(x){`
	`19`	`+if(typeofx!=='string'&&typeofx!=='number'){`
	`20`	`+thrownewTypeError('Input must be a string or a number')`
	`21`	`+}`
	`22`	`+`
	`23`	`+// Convert x to string whether it's number or string`
	`24`	`+conststring=x.toString()`
	`25`	`+constlength=string.length`
	`26`	`+`
	`27`	`+if(length===1)returntrue`
	`28`	`+`
	`29`	`+// Apply two pointers technique to compare first and last elements on each iteration`
	`30`	`+for(letstart=0,end=length-1;start<end;start++,end--){`
	`31`	`+// Early return if compared items are different, input is not a palindrome`
	`32`	`+if(string[start]!==string[end])returnfalse`
	`33`	`+}`
	`34`	`+// If early return in condition inside for loop is not reached, then input is palindrome`
	`35`	`+returntrue`
	`36`	`+}`

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	`1`	`+import{isPalindromeIterative}from'../IsPalindrome'`
	`2`	`+`
	`3`	`+describe('isPalindrome',()=>{`
	`4`	`+it('expects to return true with empty string',()=>{`
	`5`	`+expect(isPalindromeIterative('')).toEqual(true)`
	`6`	`+})`
	`7`	`+`
	`8`	`+it('expects to return true when length of input is 1',()=>{`
	`9`	`+constnumberInput=6`
	`10`	`+conststringInput='a'`
	`11`	`+expect(isPalindromeIterative(numberInput)).toEqual(true)`
	`12`	`+expect(isPalindromeIterative(stringInput)).toEqual(true)`
	`13`	`+})`
	`14`	`+`
	`15`	`+it('expects to return true when input is palindrome',()=>{`
	`16`	`+expect(isPalindromeIterative(121)).toEqual(true)`
	`17`	`+expect(isPalindromeIterative('yooy')).toEqual(true)`
	`18`	`+expect(isPalindromeIterative('19noon91')).toEqual(true)`
	`19`	`+expect(isPalindromeIterative('!tyyt!')).toEqual(true)`
	`20`	`+})`
	`21`	`+`
	`22`	`+it('expects to return false when input is not palindrome',()=>{`
	`23`	`+expect(isPalindromeIterative('hello')).toEqual(false)`
	`24`	`+expect(isPalindromeIterative(189)).toEqual(false)`
	`25`	`+expect(isPalindromeIterative('!*98[!')).toEqual(false)`
	`26`	`+})`
	`27`	`+`
	`28`	`+it('expects to throw error when input is not a string or a number',()=>{`
	`29`	`+expect(()=>isPalindromeIterative(undefined)).toThrowError()`
	`30`	`+expect(()=>isPalindromeIterative({key:'val'})).toThrowError()`
	`31`	`+expect(()=>isPalindromeIterative([])).toThrowError()`
	`32`	`+})`
	`33`	`+})`

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