题解 | #删除字符串中出现次数最少的字符#

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        while (sc.hasNext()) {
            String str = sc.next();
            HashMap<Character, Integer> map = new HashMap<>();
            for (int i = 0; i < str.length() - 1; i++) {
                for (int j = i + 1; j < str.length(); j++) {
                    if(! map.containsKey(str.charAt(i))){
                        map.put(str.charAt(i),1);
                    }
                    if(str.charAt(i) == str.charAt(j)){
                        map.put(str.charAt(i),map.get(str.charAt(i))+1);
                    }else{
                        continue;
                    }
                }
            }
            int min = Integer.MAX_VALUE;
            for(int m : map.values()){
                min = Math.min(min,m);
            }
            StringBuilder sb = new StringBuilder();
            for (int i = 0; i < str.length(); i++) {
                if(map.get(str.charAt(i)) != min){
                    sb.append(str.charAt(i));
                }
            }
            System.out.println(sb.toString());
        }
    }
}