242 Valid Anagram
Problem Statement
Given two strings s and t, return true if t is an anagram of s, and false otherwise.
An Anagram is a word or phrase formed by rearranging the letters of a different word or phrase, typically using all the original letters exactly once.
Input: s = "anagram", t = "nagaram"
Output: true
Approach
- Create a Hashmap for characters
- Loop through the string, grab left and right Char.
- For Left char we either increase or set to 1, For Right Char we either decrease or set to -1.
- One final for...in loop through hashmap keys, if their value isn't 0 return false, otherwise outside of loop return true
Solution
const isAnagram = (s, t) => {
if (s.length !== t.length) return false;
let charCount = {};
for (let i = 0; i < s.length; i++) {
const charS = s[i];
const charT = t[i];
charCount[charS] = charCount[charS] ? charCount[charS] + 1 : 1;
charCount[charT] = charCount[charT] ? charCount[charT] - 1 : -1;
}
for (let key in charCount) {
if (charCount[key] !== 0) {
return false;
}
}
return true;
};
Questions
- If using a hashmap to check if two words are anagrams, what would be the keys and the values in the hashmap?