Problem:
Score : 300 points

Problem Statement

We have N switches with "on" and "off" state, and M bulbs. The switches are numbered 1 to N, and the bulbs are numbered 1 to M.

Bulb i is connected to k_i switches: Switch s_{i1}, s_{i2}, ..., and s_{ik_i}. It is lighted when the number of switches that are "on" among these switches is congruent to p_i modulo 2.

How many combinations of "on" and "off" states of the switches light all the bulbs?

Constraints

1 \leq N, M \leq 10

1 \leq k_i \leq N

1 \leq s_{ij} \leq N

s_{ia} \neq s_{ib} (a \neq b)

p_i is 0 or 1.

All values in input are integers.

Input

Input is given from Standard Input in the following format:

N M
k_1 s_{11} s_{12} ... s_{1k_1}
:
k_M s_{M1} s_{M2} ... s_{Mk_M}
p_1 p_2 ... p_M

Output

Print the number of combinations of "on" and "off" states of the switches that light all the bulbs.

Sample Input 1

2 2
2 1 2
1 2
0 1

Sample Output 1

1

Bulb 1 is lighted when there is an even number of switches that are "on" among the following: Switch 1 and 2.

Bulb 2 is lighted when there is an odd number of switches that are "on" among the following: Switch 2.

There are four possible combinations of states of (Switch 1, Switch 2): (on, on), (on, off), (off, on) and (off, off). Among them, only (on, on) lights all the bulbs, so we should print 1.

Sample Input 2

2 3
2 1 2
1 1
1 2
0 0 1

Sample Output 2

0

Bulb 1 is lighted when there is an even number of switches that are "on" among the following: Switch 1 and 2.

Bulb 2 is lighted when there is an even number of switches that are "on" among the following: Switch 1.

Bulb 3 is lighted when there is an odd number of switches that are "on" among the following: Switch 2.

Switch 1 has to be "off" to light Bulb 2 and Switch 2 has to be "on" to light Bulb 3, but then Bulb 1 will not be lighted. Thus, there are no combinations of states of the switches that light all the bulbs, so we should print 0.

Sample Input 3

5 2
3 1 2 5
2 2 3
1 0

Sample Output 3

8

Solution in Java8 (OpenJDK 1.8.0) (judge verdict: Accepted)

import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        int n = in.nextInt();
        int m = in.nextInt();
        Light[] lights = new Light[m];
        for(int i=0; i<m; i++) {
            Light l = new Light();
            int k = in.nextInt();
            int[] s = new int[k];
            for(int j=0; j<k; j++) {
                s[j] = in.nextInt();
            }
            l.s = s;
            lights[i] = l;
        }
        for(int i=0; i<m; i++) {
            lights[i].p = in.nextInt();
        }

        int attempts = 1 << n;
        int result = 0;
        for(int i=0; i<attempts; i++) {
            boolean isAllOn = true;
            for(int j=0; j<m; j++) {
                if(!lights[j].isOn(i)) {
                    isAllOn = false;
                    break;
                }
            }
            if(isAllOn) {
                result++;
            }
        }
        System.out.println(result);
    }
}
class Light {
    int[] s;
    int p;
    public boolean isOn(int switches) {
        int c = 0;
        for(int i=0; i<this.s.length; i++) {
            if((switches & (1<<(this.s[i]-1))) > 0) {
                c++;
            }
        }
        return (c%2 == this.p);
    }
}