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#2697 - Lexicographically Smallest Palindrome
Problem Description
You are given a string s consisting of lowercase English letters, and you are allowed to perform operations on it. In one operation, you can replace a character in s with another lowercase English letter.
Your task is to make s a palindrome with the minimum number of operations possible. If there are multiple palindromes that can be made using the minimum number of operations, make the lexicographically smallest one.
A string a is lexicographically smaller than a string b (of the same length) if in the first position where a and b differ, string a has a letter that appears earlier in the alphabet than the corresponding letter in b.
Return the resulting palindrome string.
Solution
/**
* @param {string} s
* @return {string}
*/
var makeSmallestPalindrome = function(s) {
const chars = s.split('');
let left = 0;
let right = s.length - 1;
while (left < right) {
if (chars[left] !== chars[right]) {
chars[left] = chars[right] = chars[left] < chars[right] ? chars[left] : chars[right];
}
left++;
right--;
}
return chars.join('');
};