题解 | #删除字符串中出现次数最少的字符#

import java.util.*;

public class Main {
    public Main() {

    }
    public String deleteLessChar(String str) {
        //Map记录字母出现个数
        Map<Character, Integer> map = new HashMap<>();
        for(char ch : str.toCharArray()) {
            map.put(ch, map.getOrDefault(ch, 0) + 1);
        }
        int min = Integer.MAX_VALUE;
        for(int times : map.values()) {
            min = Math.min(min, times);
        }

        StringBuilder res = new StringBuilder();
        for (char ch : str.toCharArray()) {
            if(map.get(ch) != min) {
                res.append(ch);
            }
        }
        return res.toString();
    }

    public static void main(String args[]) {
        Main main = new Main();
        Scanner sc = new Scanner(System.in);
        while(sc.hasNextLine()) {
            String str = sc.nextLine();
            String res = main.deleteLessChar(str);
            System.out.println(res);
        }
    }
}