#include <bits/stdc++.h>

using namespace std;
#define ll long long
#define pii pair<int, int>
#define ld long double
#define all(a) (a).begin(), (a).end()

unsigned long long get_reversed_32_bits(unsigned long long mask2) {
    unsigned long long mask3 = 0;
    // reversed mask2
    for (unsigned long long i = 0; i < 4; ++i) {
        unsigned long long cur = (mask2 >> (8ULL * i)) & 255ULL;
        mask3 += cur << (8ULL * (3ULL - i));
    }
    return mask3;
}

vector<unsigned long long> encode(vector<unsigned long long> A) {
    unsigned long long n = A.size();
    vector<int> bits;
    auto add_bits = [&bits](unsigned long long x) {
        for (unsigned long long i = 0; i < 64; ++i)
            bits.emplace_back((x >> i) & 1ull);
    };
    add_bits(n);
    for (auto x : A)
        add_bits(x);
    auto get_bit = [&bits](int i) -> unsigned long long {
        if (i < bits.size())
            return bits[i];
        return 0;
    };
    
    int i = 0;
    vector<unsigned long long> ans;
    while (i < bits.size()) {
        unsigned long long mask1 = 0;
        for (unsigned long long j = 0; j < 31; ++j) {
            mask1 += (get_bit(i + j) << j);
        }
        unsigned long long mask2 = 0;
        for (unsigned long long j = 0; j < 31; ++j) {
            mask2 += (get_bit(i + 31 + j) << j);
        }
        if (mask1 == mask2) {
            mask1 += (get_bit(i + 62) << 31ULL);
            mask2 += (get_bit(i + 62) << 31ULL);
        } else if (mask1 < mask2) {
            mask1 += (get_bit(i + 62) << 31ULL);
            mask2 += (1ULL << 31ULL);
        } else {
            mask1 += (0ULL << 31ULL);
            mask2 += (get_bit(i + 62) << 31ULL);
        }
        unsigned long long mask3 = get_reversed_32_bits(mask2);
        ans.emplace_back(mask1 + (mask3 << 32ULL));
        i += 63;
    }
    return ans;
}

vector<unsigned long long> decode(vector<unsigned long long> A) {
    vector<unsigned long long> bits;
    for (auto x : A) {
        unsigned long long mask1 = x & ((1ull << 32ull) - 1ull);
        unsigned long long mask3 = (x >> 32ull) & ((1ull << 32ull) - 1ull);
        // reverse mask3
        unsigned long long mask2 = get_reversed_32_bits(mask3);
        unsigned long long last_bit1 = mask1 >> 31ull;
        unsigned long long last_bit2 = mask2 >> 31ull;
        mask1 ^= last_bit1 << 31ull;
        mask2 ^= last_bit2 << 31ull;

        bool should_reverse = false;
        unsigned long long real_last_bit = 0;
        if (mask1 > mask2) {
            if (last_bit1)
                should_reverse = true;
            real_last_bit = last_bit2;
        } else {
            if (!last_bit2)
                should_reverse = true;
            real_last_bit = last_bit1;
        }
        //cerr << should_reverse << '\n';
        if (should_reverse) {
            swap(mask1, mask2);
        }
        for (unsigned long long i = 0; i < 31; ++i)
            bits.emplace_back((mask1 >> i) & 1ull);
        for (unsigned long long i = 0; i < 31; ++i)
            bits.emplace_back((mask2 >> i) & 1ull);
        bits.emplace_back(real_last_bit);
    }
    auto parse_bits = [&bits](int i) {
        unsigned long long ans = 0;
        for (unsigned long long j = 0; j < 64; ++j)
            ans += bits[i + j] << j;
        return ans;
    };
    unsigned long long n = parse_bits(0);
    vector<unsigned long long> ans(n);
    int cur = 64;
    for (unsigned long long i = 0; i < n; ++i) {
        ans[i] = parse_bits(cur);
        cur += 64;
    }
    return ans;
}

vector<unsigned long long> do_something(vector<unsigned long long> A) {
    for (unsigned long long& x : A) {
        if (rand() % 2) {
            unsigned long long kek = 0;
            for (unsigned long long i = 0; i < 8; ++i) {
                unsigned long long block = (x >> (i * 8ull)) & 255ull;
                kek += (block << ((7ull - i) * 8ull));
            }
            x = kek;
        }
    }
    return A;
}

signed main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    string s;
    cin >> s;
    
    if (s == "encode") {
        unsigned long long n;
        cin >> n;
        vector<unsigned long long> A(n);
        for (int i = 0; i < n; ++i)
            cin >> A[i];
        /*for (int i = 0; i < 1000; ++i) {
            auto ans = encode(A);
            auto B = do_something(ans);
            auto C = decode(B);
            if (A != C) {
                for (unsigned long long x : A)
                    cerr << x << ' ';
                cerr << '\n';
                for (unsigned long long x : ans)
                    cerr << x << ' ';
                cerr << '\n';
                for (unsigned long long x : B)
                    cerr << x << ' ';
                cerr << '\n';
                for (unsigned long long x : C)
                    cerr << x << ' ';
                cerr << '\n';
            }
            assert(A == C);
        }*/
        auto ans = encode(A);
        cout << ans.size() << '\n';
        for (auto x : ans)
            cout << x << ' ';
        cout << '\n';
    } else {
        int k;
        cin >> k;
        vector<unsigned long long> A(k);
        for (int i = 0; i < k; ++i) {
            cin >> A[i];
        }
        auto ans = decode(A);
        for (auto x : ans)
            cout << x << ' ';
        cout << '\n';
    }
    return 0;
}