#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
#include <bits/stdc++.h>
#include <stdlib.h>
#include <atcoder/all>
using namespace atcoder;
using namespace std;
#define rep(i, a, n) for(ll i = a; i < n; i++)
#define rrep(i, a, n) for(ll i = a; i >= n; i--)
#define inr(l, x, r) (l <= x && x < r)
#define ll long long
#define ld long double
#define pii pair<int, int>
#define pll pair<ll, ll>
#define all(x) (x).begin(), (x).end()
//constexpr ll MOD = 1000000007;
constexpr ll MOD = 998244353;
constexpr int IINF = 1001001001;
constexpr ll INF = 1LL<<60;
template<class t,class u> void chmax(t&a,u b){if(a<b)a=b;}
template<class t,class u> void chmin(t&a,u b){if(b<a)a=b;}

using mint = modint998244353;

ll gcd(ll a, ll b){
    if(a%b == 0){
      return b;
    }else{
      return gcd(b, a%b);
    }
}

ll lcm(ll a, ll b){
    return a*b / gcd(a, b);
}

ll powMod(ll x, ll n, ll mod) {
    if (n == 0) return 1 % mod;
    ll val = powMod(x, n / 2, mod);
    val *= val;
    val %= mod;
    if (n % 2 == 1) val *= x;
    return val % mod;
}

int main() {
    cout << fixed << setprecision(15);
    ll n, x, q; cin >> n >> x >> q;
    ld ans = 0;

    rep(i,0,q){
        ll m; cin >> m;
        ll f1 = 0, f2 = 0;
        set<ll> st;
        rep(j,0,m){
            ll a; cin >> a;
            if(a == x) f1 = 1;
            st.insert(a);
        }
        if(st.size() != m) f2 = 1;
        if(f1) ans += 1;
        else if(f2) ans += 0.5;
    }

    cout << ans << endl;

    return 0;
}