tj

#include <iostream>
#include <string>
#include <vector>
#include <algorithm>
using namespace std;
struct LetterCount {
    char letter;
    int count;
};
bool compare(const LetterCount& a, const LetterCount& b) {
    if (a.count != b.count) {
        return a.count > b.count;
    }
    return a.letter < b.letter;
}
int main() {
    string input;
    cin >> input;
    vector<int> count(26, 0);
    for (char c : input) {
        count[c - 'a']++;
    }
    vector<LetterCount> letterCounts;
    for (int i = 0; i < 26; i++) {
        if (count[i] > 0) {
            letterCounts.push_back({static_cast<char>('a' + i), count[i]});
        }
    }
    sort(letterCounts.begin(), letterCounts.end(), compare);
    for (size_t i = 0; i < letterCounts.size(); i++) {
        if (i > 0) {
            cout << " ";
        }
        cout << letterCounts[i].letter;
    }
    cout << endl;
    return 0;
}