#include<bits/stdc++.h>
using namespace std;

int main(){
	int N,X,Q;
	cin >> N >> X >> Q;
	int ans=0;
	for(;Q--;){
		int M;
		cin >> M;
		vector<int> F(M);
		for(int i=0;i<M;i++) cin >> F[i];
		sort(F.begin(),F.end());
		F.erase(unique(F.begin(),F.end()),F.end());
		if(binary_search(F.begin(),F.end(),X)) ans+=2;
		else if((int)(F.size())!=M) ans++;
	}
	cout << ans/2;
	if(ans&1) cout << ".5";
	cout << '\n';
}