long winningLotteryTicket(vector<string> tickets) {
    // A map to store the frequency of each bitmask
    unordered_map<int, long> bitmask_count;
    
    // Process each ticket and compute its bitmask
    for (const string& ticket : tickets) {
        int bitmask = 0;
        
        // Mark the digits that appear in the ticket
        for (char c : ticket) {
            bitmask |= (1 << (c - '0'));
        }
        
        // Increment the count for this bitmask
        bitmask_count[bitmask]++;
    }
    
    long result = 0;
    
    // Now check pairs of bitmasks
    for (auto it1 = bitmask_count.begin(); it1 != bitmask_count.end(); ++it1) {
        for (auto it2 = next(it1); it2 != bitmask_count.end(); ++it2) {
            if ((it1->first | it2->first) == 1023) {
                result += it1->second * it2->second;
            }
        }
    }
    
    // Check the cases where both bitmasks are the same
    for (auto it1 = bitmask_count.begin(); it1 != bitmask_count.end(); ++it1) {
        if ((it1->first | it1->first) == 1023) {
            result += (it1->second * (it1->second - 1)) / 2;
        }
    }

    return result;
}