题解 | #字符统计#

#include <iostream>
#include <string>
#include <vector>
#include <algorithm>
using namespace std;

int main() {
    string str;
    while (cin >> str) {
        // 统计每个字符出现次数
        vector<pair<char, int>> counts;
        vector<bool> visited(128, false);  // ASCII码范围
        
        for (char c : str) {
            if (!visited[c]) {
                visited[c] = true;
                int count = 0;
                for (char ch : str) {
                    if (ch == c) count++;
                }
                counts.push_back({c, count});
            }
        }
        
        // 排序：先按次数降序，次数相同按ASCII码升序
        sort(counts.begin(), counts.end(), 
             [](const pair<char, int>& a, const pair<char, int>& b) {
                 if (a.second != b.second) return a.second > b.second;
                 return a.first < b.first;
             });
        
        // 输出结果
        string result;
        for (const auto& p : counts) {
            result += p.first;
        }
        cout << result << endl;
    }
    return 0;
}

import java.util.*;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        while (sc.hasNext()) {
            String str = sc.nextLine();
            
            // 统计每个字符出现次数
            Map<Character, Integer> countMap = new HashMap<>();
            for (char c : str.toCharArray()) {
                countMap.put(c, countMap.getOrDefault(c, 0) + 1);
            }
            
            // 转换为列表便于排序
            List<Map.Entry<Character, Integer>> list = 
                new ArrayList<>(countMap.entrySet());
            
            // 排序：先按次数降序，次数相同按ASCII码升序
            Collections.sort(list, (a, b) -> {
                if (!a.getValue().equals(b.getValue())) {
                    return b.getValue() - a.getValue();
                }
                return a.getKey() - b.getKey();
            });
            
            // 输出结果
            StringBuilder result = new StringBuilder();
            for (Map.Entry<Character, Integer> entry : list) {
                result.append(entry.getKey());
            }
            System.out.println(result.toString());
        }
    }
}

while True:
    try:
        s = input()
        
        # 统计每个字符出现次数
        char_count = {}
        for c in s:
            char_count[c] = char_count.get(c, 0) + 1
        
        # 按照次数和ASCII码排序
        sorted_chars = sorted(char_count.items(), 
                            key=lambda x: (-x[1], x[0]))
        
        # 输出结果
        result = ''.join(char for char, _ in sorted_chars)
        print(result)
        
    except:
        break