#include<stdio.h>
int h[200005], l;
int comp_h(int a, int b)
{
	if (h[a] > h[b])
		return 1;
	else
		return -1;
}
void swap_h(int a, int b)
{
	int f = h[a];
	h[a] = h[b];
	h[b] = f;
	return;
}
void push(int ne)
{
	h[l] = ne;
	int p = l++;
	for (; p > 0; p = (p - 1) / 2)
		if (comp_h((p - 1) / 2, p) > 0)
			swap_h((p - 1) / 2, p);
	return;
}
int pop()
{
	swap_h(0, --l);
	int p = 0;
	for (;;)
	{
		if (2 * p + 2 < l)
		{
			if (comp_h(2 * p + 1, 2 * p + 2) > 0)
			{
				if (comp_h(p, 2 * p + 2) > 0)
					swap_h(p, 2 * p + 2);
				p = 2 * p + 2;
			}
			else
			{
				if (comp_h(p, 2 * p + 1) > 0)
					swap_h(p, 2 * p + 1);
				p = 2 * p + 1;
			}
		}
		else if (2 * p + 1 < l)
		{
			if (comp_h(p, 2 * p + 1) > 0)
				swap_h(p, 2 * p + 1);
			p = 2 * p + 1;
		}
		else
			break;
	}
	return h[l];
}
int f[200005];
int main()
{
	int n, x, q;
	scanf("%d %d %d", &n, &x, &q);
	int i, m;
	int ans = 0, v;
	for (; q > 0; q--)
	{
		scanf("%d", &m);
		for (i = 0; i < m; i++)
			scanf("%d", &f[i]);
		l = 0;
		for (i = 0; i < m; i++)
			push(f[i]);
		for (i = 0; i < m; i++)
			f[i] = pop();
		v = 0;
		for (i = 1; i < m; i++)
			if (f[i - 1] == f[i])
				v = 1;
		for (i = 0; i < m; i++)
			if (f[i] == x)
				v = 2;
		ans += v;
	}
	if (ans % 2 > 0)
		printf("%d.5\n", ans / 2);
	else
		printf("%d\n", ans / 2);
	return 0;
}