Problem

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.

Example 1:

Input: s = "anagram", t = "nagaram" Output: true

Example 2:

Input: s = "rat", t = "car" Output: false

Solution

Simple sorted solution:

class Solution:
    def isAnagram(self, s: str, t: str) -> bool:
        return sorted(s) == sorted(t)

This is O(n log n) which is a bit slow

Solution 2

We can use Dicts for this, like:

class Solution:
    def isAnagram(self, s: str, t: str) -> bool:
        d1, d2 = {}, {}
        for i in s:
            d1[i] = d1.get(i, 0) + 1
        for i in t:
            d2[i] = d2.get(i, 0) + 1
        return d1 == d2

Solution 3

The Counters library is very handy for leetcode and we can make dicts with it like:

class Solution:
    def isAnagram(self, s: str, t: str) -> bool:
        return collections.Counter(s) == collections.Counter(t)