We are required to write a JavaScript function that takes in a string. The function should return true if the string is a palindrome string, false otherwise.
Palindrome strings are those strings that reads the same from back and front.
For example − 'madam', 'dad', 'abcdcba'
Our only condition is that we cannot use any inbuilt string method or convert the string to array.
Example
const str = 'madam';
const isPalindrome = (str = '') => {
const { length } = str;
let start = 0, end = length - 1; while(start < end){
const leftChar = str[start];
const rightChar = str[end];
if(leftChar !== rightChar){
return false;
};
start++;
end--;
};
return true;
};
console.log(isPalindrome(str));
console.log(isPalindrome('avsssvsa'));Output
And the output in the console will be −
true false