题解 | #找出字符串中第一个只出现一次的字符#

package main

import (
	"fmt"
	"strings"
)

func main() {
	var str string
	fmt.Scan(&str)

	for _, s := range str {
		if strings.Index(str, string(s)) == strings.LastIndex(str, string(s)) {
			fmt.Println(string(s))

			return
		}
	}

	fmt.Println(-1)
}