#include <iostream>
#include <map>
#include <vector>
using namespace std;

int main() {
    int K;
    cin >> K;
    for (int set = 1; set <= K; set++) {
        printf("Data Set %d:\n", set);
        long long n;
        string p;
        cin >> n >> p;
        vector<int> symbols;
        map<int,char> char_from_symbol;
        int symbol_from_char[26];
        for (long long base = 2; base <= 1e6; base++) {
            long long ncopy = n;
            symbols.clear();
            while (ncopy > 0) {
                symbols.push_back(ncopy % base);
                ncopy /= base;
            }
            if (symbols.size() < p.size())
                break;
            char_from_symbol.clear();
            for (int i = 0; i < 10; i++)
                symbol_from_char[i] = -1;
            bool matched = true;
            for (int i = symbols.size() - 1, char_pos = 0; i >= 0; i--, char_pos++) {
                char pchar = p[char_pos % p.size()];
                if (symbols[i] == symbol_from_char[pchar - 'a'])
                    continue;
                if (-1 == symbol_from_char[pchar - 'a'] &&
                    0 == char_from_symbol.count(symbols[i])) {
                    symbol_from_char[pchar - 'a'] = symbols[i];
                    char_from_symbol.insert(make_pair(symbols[i], pchar));
                    continue;
                }
                matched = false;
                break;
            }
            if (matched) {
                printf("%d\n%d", (int)base, symbols[symbols.size() - 1]);
                for (int i = symbols.size() - 2; i >= 0; i--)
                    printf(" %d", symbols[i]);
                goto DONE;
            }
        }
        printf("No such base.");
    DONE:
        printf("\n\n");
    }
}