Find Words That Can Be Formed by Characters

package main

import (
	"fmt"
	"maps"
)

func countCharacters(words []string, chars string) int {
	charsMap := map[rune]int{}
	for _, ch := range chars {
		charsMap[ch]++
	}

	length := 0
	for _, w := range words {
		mapClone := maps.Clone(charsMap)
		found := true
		for _, ch := range w {
			if mapClone[ch] > 0 {
				mapClone[ch]--
			} else {
				found = false
				break
			}
		}
		if found {
			length += len(w)
		}
	}
	return length
}

func main() {
	words := []string{"cat", "bt", "hat", "tree"}
	chars := "atach"
	fmt.Println(countCharacters(words, chars)) // 6 ("cat" + "hat")
}