package uniqueschars

import (
	"unicode"
	"unicode/utf8"
)

func Unique(s string) bool {
	m := make(map[rune]struct{}, utf8.RuneCountInString(s)/2)

	for _, c := range s {
		c := unicode.ToLower(c)

		if _, ok := m[c]; ok {
			return false
		}

		m[c] = struct{}{}
	}

	return true
}