题解 | 删除字符串中出现次数最少的字符

import java.util.Scanner;
import java.util.HashMap;
public class  Main{
    public static void main(String[] args){
        Scanner sc  = new Scanner(System.in);
        String s  = sc.nextLine();
        StringBuilder sb  = new StringBuilder();
        HashMap<Character,Integer> countmap = new HashMap<>();
        for(char c : s.toCharArray()){
            countmap.put(c,countmap.getOrDefault(c,0)+ 1);
        }
        int mincount = Integer.MAX_VALUE;
        for(int count : countmap.values()){
            if(count < mincount){
                mincount  = count;
            }
        }
    for(char c : s.toCharArray()){
        if(mincount!=countmap.get(c)){
            sb.append(c);
        }
    }
    System.out.println(sb.toString());
    }
}

原本想用哈希表来去重然后统计数。后来发现哈希图有自动计数功能。