Group Anagrams

LeetCode 49 · View on LeetCode

Sort each string to create a canonical key. All anagrams produce the same sorted key, so they land in the same map bucket.

package main

import (
	"fmt"
	"sort"
)

func groupAnagrams(strs []string) [][]string {
	groups := make(map[string][]string)
	for _, s := range strs {
		b := []byte(s)
		sort.Slice(b, func(i, j int) bool { return b[i] < b[j] })
		key := string(b)
		groups[key] = append(groups[key], s)
	}
	result := make([][]string, 0, len(groups))
	for _, g := range groups {
		result = append(result, g)
	}
	return result
}

func main() {
	fmt.Println(groupAnagrams([]string{"eat", "tea", "tan", "ate", "nat", "bat"}))
	// [[eat tea ate] [tan nat] [bat]]
}