ваы

////Частотная 1
#include <fstream>
#include <string>
using namespace std;

int main() {
    ifstream input("input.txt");
    ofstream output("output.txt");
    string str;
    getline(input, str);
    const int length = 26;
    int mas[length] = { 0 };
    for (int i = 0; i < str.size(); i++)
    {
        char symb;
        symb = toupper(str[i]);
        if ('A'<=symb && symb <='Z')
        {
            mas[symb - 'A']++;
        }
    }
    for (int i = 0; i < length; i++)
    {
        output << (char)(i + 'A') << "   " << mas[i] << endl;
    }
    return 0;
}

//////////////// Частотная 2
#include <fstream>
#include <string>
using namespace std;

int main()
{
    ifstream input("input.txt");
    ofstream output("output.txt");
    string str;
    getline(input, str);
    const int length = 26;
    int mas[length] = { 0 };
    for (int i = 0; i < str.size(); i++)
    {
        char symb;
        symb = toupper(str[i]);
        if ('A' <= symb && symb <= 'Z')
        {
            mas[symb - 'A']++;
        }
    }
    int mas2[length];
    for (int i = 0; i < length; i++)
    {
        mas2[i] = i;
    }
    for (int i = 0; i < length - 1; i++)
    {
        for (int j = 0; j < length - i - 1; j++)
        {
            if (mas[j] < mas[j + 1])
            {
                swap(mas[j], mas[j + 1]);
                swap(mas2[j], mas2[j + 1]);
            }
        }
    }
    for (int i = 0; i < length && mas[i] != 0; i++)
    {
        output << (char)(mas2[i] + 'A') << "   " << mas[i] << endl;
    }
    return 0;
}