题解 | #提取不重复的整数#

package main

import (
	"fmt"
	"strconv"
)

func main() {
	var num int
	fmt.Scan(&num)
	m := make(map[byte]bool)
	str := strconv.Itoa(num)
	var ret string
	for i := len(str) - 1; i >= 0; i-- {
		if _, ok := m[str[i]]; ok {
			continue
		}
		ret += string(str[i])
		m[str[i]] = true
	}
	n, _ := strconv.Atoi(ret)
	fmt.Println(n)
}