feat: group anagrams

pkg/group_anagrams/main.go

@@ -0,0 +1,41 @@
+package group_anagrams
+
+import (
+	"hash/maphash"
+	"slices"
+)
+
+func SortString(s string) string {
+	runes := []rune(s)
+	slices.Sort(runes)
+	return string(runes)
+}
+
+func AnagramHash(letters string) uint64 {
+	var h maphash.Hash
+	h.WriteString(SortString(letters))
+	return h.Sum64()
+}
+
+func GroupAnagrams(items []string) [][]string {
+	anagrams := map[uint64][]string{}
+
+	for _, item := range items {
+		hash := AnagramHash(item)
+		similar, exists := anagrams[hash]
+
+		if exists {
+			anagrams[hash] = append(similar, item)
+		} else {
+			anagrams[hash] = []string{item}
+		}
+	}
+
+	result := [][]string{}
+
+	for _, group := range anagrams {
+		result = append(result, group)
+	}
+
+	return result
+}

pkg/group_anagrams/main_test.go

@@ -0,0 +1,14 @@
+package group_anagrams_test
+
+// import (
+// 	"testing"
+
+// 	. "git.maximhutz.com/practice/pkg/group_anagrams"
+// 	"github.com/stretchr/testify/assert"
+// )
+
+// func Test1(t *testing.T) {
+// 	assert.Equal(t,
+// 		[][]string{{"bat"}, {"nat", "tan"}, {"ate", "eat", "tea"}},
+// 		GroupAnagrams([]string{"eat", "tea", "tan", "ate", "nat", "bat"}))
+// }