## Arrays And Strings

##### Non-repeating characters in a string.

The problem is to find the first non-repeating character in a given string. The function should take a string as input and return the first non-repeating character.

135
Oct 24
##### Is the String a Palindrome?

This problem asks whether a given string is a palindrome. A palindrome is a word or phrase that is the same forwards and backwards. In this case, the input string " racecar" is a palindrome, so the output would be "true".

147
Oct 23
##### Longest Common Prefix in an Array of Strings

Given an array of strings, this problem seeks to find the longest common prefix. This can be done by comparing the first string in the array with the second string, then the second string with the third string, and so on. The longest common prefix is the substring that is shared by all strings in the array.

137
Oct 23
##### Find the length of the longest substring without repeating characters.

This problem asks you to find the length of the longest substring in a given string without any repeating characters. Examples are provided to illustrate how this would work. Note that the answer must be a substring, not just a subsequence.

137
Oct 23
##### Unique Characters in a String

This problem asks you to implement an algorithm to determine if a string has all unique characters. This can be done by keeping track of which characters have been seen so far in a hash set, and then checking if the character being processed is already in the set. If it is, then we know that the string does not have all unique characters.

186
Oct 22
##### "Is the String a Palindrome?"

This problem deals with determining whether or not a given string is a palindrome. This is done by considering only alphanumeric characters and ignoring cases. An empty string is considered a valid palindrome.

193
Oct 22
##### Is It a Permutation of a Palindrome?

This problem asks whether a given string is a permutation of a palindrome. A palindrome is a word or phrase that is the same forwards and backwards, while a permutation is a rearrangement of letters. The palindrome does not need to be limited to just dictionary words.

156
Oct 22
##### Is the string a permutation of a palindrome?

This function checks if a given string is a permutation of a palindrome. A palindrome is a word or phrase that is the same forwards and backwards, while a permutation is a rearrangement of letters. The palindrome does not need to be limited to just dictionary words.

136
Oct 22