情况考虑不周 非边界值

https://leetcode-cn.com/problems/valid-anagram/

异或运算找重复值

func f(s string) int {
	n := len(s)
	var a int
	a = 1
	for i := 0; i < n; i++ {
		a ^= int(rune(s[i]))
	}
	return a
}
func isAnagram(s string, t string) bool {
	return f(s)^f(t) == 0
}