#include "sort.h"
#include <iostream>
#include <algorithm>

using namespace std;

const int MAX_CHAR = 26;

string sortString(const string& input) {
    int charCount[MAX_CHAR] = {0};

    for (char i: input)
        charCount[i - 'a']++;

    string output;
    for (int i = 0; i < MAX_CHAR; i++)
        for (int j = 0; j < charCount[i]; j++)
            output += (char) (i + 'a');

    return output;
}