# Palindrome in JavaScript – GeeksforGeeks

We are going to perceive test whether or not a given worth is a palindrome or not in JavaScript. A palindrome is a price that reads the identical from backward or ahead. To carry out this test we are going to use the next approaches:

Method 1:

• Iterate over the string from ahead and backward path
• Examine if the character match
• Return false for the primary character that doesn’t match
• Return true if all of the comparisons are carried out and the characters match

Instance: This instance implements the above strategy.

## Javascript

 `perform` `isPalindrome(str) {` `    ``var` `j = str.length-1` `    ``for``(``var` `i=0; i

Output:

```true
true
false```

Method 2:

• Initialize a variable and retailer the reverse of the worth in it utilizing for loop
• Examine the unique worth with the reversed worth
• If each values are equal return true else return false

Instance: This instance implements the above strategy.

## Javascript

 `perform` `isPalindrome(str) {` `    ``var` `rev=``""``;` `    ``for``(``var` `i=str.length-1; i>=0; i--){` `        ``rev+= str[i];` `    ``}` `    ``if``(rev==str){` `        ``return` `true` `    ``} ``else``{` `        ``return` `false``;` `    ``}` `}` ` `  `var` `str1 = ``"racecar"``;` `var` `str2 = ``"nitin"``;` `var` `str3 = ``"Rama"``;` ` `  `console.log(isPalindrome(str1));` `console.log(isPalindrome(str2));` `console.log(isPalindrome(str3));`

Output:

```true
true
false```

Method 3:

• Use inbuilt string strategies like cut up() to separate the string into characters array
• Reverse the array utilizing reverse() methodology
• Be a part of the array right into a string utilizing be a part of() methodology
• Retailer this worth inside one other variable
• Examine the values and return true if each are equal

Instance: This instance implements the above strategy on string

## Javascript

 `perform` `isPalindrome(str) {` `    ``var` `rev=str.cut up(``""``).reverse().be a part of(``""``);` ` `  `    ``if``(rev == str){` `        ``return` `true` `    ``}` `    ``return` `false` `                `  `}` ` `  `var` `str1 = ``"racecar"``;` `var` `str2 = ``"nitin"``;` `var` `str3 = ``"Rama"``;` ` `  `console.log(isPalindrome(str1));` `console.log(isPalindrome(str2));` `console.log(isPalindrome(str3));`

Output:

```true
true
false```

Instance: This instance implements the above strategy to Quantity

## Javascript

 `perform` `isPalindrome(num) {` `    ``var` `str = num.toString();` `    ``var` `rev=str.cut up(``""``).reverse().be a part of(``""``);` ` `  `    ``if``(rev == str){` `        ``return` `true` `    ``}` `    ``return` `false` `                `  `}` ` `  `var` `str1 = 1234321;` `var` `str2 = 112211;` `var` `str3 = 12345;` ` `  `console.log(isPalindrome(str1));` `console.log(isPalindrome(str2));` `console.log(isPalindrome(str3));`

Output: The Quantity is first transformed to a string after which in contrast utilizing the earlier strategy

```true
true
false```

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