【华为OD机试真题】103、最大数字

package main

import (
	"fmt"
	"strconv"
)

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

	inputNums := make([]int, len(input))
	charMap := make(map[int]int)
	outputNums := make([]int, 0)

	for index, i := range input {
		inputNum, _ := strconv.Atoi(string(i))
		inputNums[index] = inputNum
		charMap[inputNum]++
	}

	for i, num := range inputNums {

		if charMap[num] > 2 {
			if i < len(inputNums)-1 {
				nextNum := inputNums[i+1]
				if num <= nextNum {
					charMap[num]--
				} else {
					outputNums = append(outputNums, num)
				}
			}

		} else {
			outputNums = append(outputNums, num)
		}

	}

	outStr := ""
	for _, num := range outputNums {
		outStr = fmt.Sprintf("%s%d", outStr, num)
	}

	fmt.Println(outStr)

}