Group Anagrams
Explore how to group strings that are anagrams by tracking frequencies of characters. This lesson helps you understand the problem and develop efficient solutions using data tracking patterns to solve frequency-related tasks in coding interviews.
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Statement
Given a list of strings strs, group together all strings that are anagrams of each other.
An anagram is a string formed by rearranging the letters of another string, using all original letters exactly once. For example, “eat”, “tea”, and “ate” are anagrams.
Return a list of groups, where each group contains strings that are anagrams of each other.
Note: The order of the groups and the order of strings within each group does not matter.
Constraints:
Let strs be the list of strings given as input to find the anagrams.
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strs.length -
strs[i].length strs[i]consists of lowercase English letters.
Examples
Understand the problem
Let’s take a moment to make sure you've correctly understood the problem. The quiz below helps you check if you're solving the correct problem:
Group Anagrams
What is the output if the following list is given as input?
[‘bat’, ‘tab’, ‘tan’, ‘at’]
[[‘at’], [‘bat’], [‘tab’], [‘tan’]]
[[‘at’, ‘bat’]], [[‘tab’, tan’]]
[[‘at’, ‘bat’, ‘tab’, tan’]]
[[‘tab’, ‘bat’]], [‘tan’], [‘at’]]
Figure it out!
We have a game for you to play. Rearrange the logical building blocks to develop a clearer understanding of how to solve this problem.
Try it yourself
Implement your solution in the following coding playground.
import java.util.*;class GroupAnagrams {public static List<List<String>> groupAnagrams(String[] strs){// Replace this placeholder return statement with your codereturn new ArrayList<>();}}