#include <iostream>
#include <vector>
#include <algorithm>

#define int long long

using namespace std;

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);

    int test_cases;
    cin >> test_cases;

    while(test_cases--) {
        int str_len, num_positions;
        cin >> str_len >> num_positions;

        string input_str, replacement_chars;
        cin >> input_str;

        vector<int> positions(num_positions);
        vector<char> replacement_list(num_positions);

        for(int i = 0; i < num_positions; ++i) {
            cin >> positions[i];
            input_str[positions[i] - 1] = '*';
        }

        cin >> replacement_chars;

        for(int i = 0; i < num_positions; ++i) {
            replacement_list[i] = replacement_chars[i];
        }

        sort(replacement_list.begin(), replacement_list.end());

        int idx = 0;
        for(int i = 0; i < str_len; ++i) {
            if(input_str[i] == '*') {
                input_str[i] = replacement_list[idx];
                ++idx;
            }
        }

        cout << input_str << '\n';
    }

    return 0;
}