#include <vector>
#include <cmath>
#include "optimization.h"
#include <tuple>
#include <bitset>

using namespace std;
using ind = size_t;

constexpr int N = 202;


struct Gauss {
    vector<bitset<N>> A;
    vector<int> col;
    ind n, m;

    Gauss(ind n, ind m) : n(n), m(m) {}

    int add(bitset<N> a) {
        for (ind i = 0; i < A.size(); ++i) {
            if (a[col[i]]) {
                a ^= A[i];
            }
        }
        ind i = 0;
        while (i < n && !a[i]) i++;
        if (i == n) return 0;
        if(i == n - 1) return -1;
        A.push_back(std::move(a));
        col.push_back(i);
        return 1;
    }

    bitset<N> getX() {
        ind k = A.size();
        bitset<N> x;
        for(int i = k - 1; i >= 0; i--) {
            x[col[i]] = A[i][m];
            for(ind j = i + 1; j < k; j++) {
                x[col[i]] = x[col[i]] ^ (A[i][col[j]] & x[col[j]]);
            }
        }
        return x;
    }
};

int main() {
    int n = readInt();
    Gauss g(n + 1, n);
    vector<bitset<N>> m(n);
    for (int i = 0; i < n; ++i) {
        int k = readInt();
        for (int j = 0; j < k; ++j) {
            int b = readInt() - 1;
            m[b][i] = true;
        }
    }
    for (int i = 0; i < n; ++i) {
        m[i][n] = readInt() == 1;
    }
    for(auto& v : m) {
        if(g.add(v) == -1) {
//            writeInt(-1, '\n');
//            return 0;
        }
    }
    auto x = g.getX();
    for(auto v : m) {
        bool a = v[n];
        for(int i = 0; i < n; i++) {
            a ^= v[i] & x[i];
        }
        if(a != 0) {
            writeInt(-1, '\n');
            return 0;
        }
    }
    writeInt(x.count(), '\n');
    for (int i = 0; i < n; ++i) {
        if(x[i]) {
            writeInt(i + 1, ' ');
        }
    }
    return 0;
}