#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define ld long double
#define ull unsigned long long
#define pii pair<int, int>
#define pll pair<ll, ll>
#define fi first
#define se second
const int N = 5e5 + 5;
int x[N], sum[N];
vector<int> a[N];
vector<pair<int, int>> v, ans1, ans2;
int main() {
//ios_base::sync_with_stdio(false); cin.tie(NULL);
int l, r;
cin >> l >> r;
for (int i = 1; i <= r; i++) {
cin >> x[i];
for (int j = 0; j < x[i]; j++) {
int x2;
cin >> x2;
a[i].push_back(x2);
sum[i] += x2;
}
}
for (int i = 1; i <= r; i++) {
v.clear();
if (sum[i] == l) {
ans1.push_back({1, l});
break;
}
int sum1 = 0, sum2 = sum[i];
v.push_back({sum1 + 1, l - sum2});
for (int j = 0; j < x[i]; j++) {
sum1 += a[i][j], sum2 -= a[i][j];
v.push_back({sum1 + 1, l - sum2});
}
for (int j = 1; j < (int)v.size(); j++) {
if (v[j].fi <= v[j - 1].se) continue;
ans1.push_back({v[j - 1].se + 1, v[j].fi - 1});
}
// cout << i << "flaw\n";
// for (auto j : v) cout << j.fi << " " << j.se << "fkwoa\n";
}
sort(ans1.begin(), ans1.end());
// for (auto i : ans1) cout << i.fi << " " << i.se << "dkawop\n";
for (auto y : ans1) {
if (ans2.empty()) ans2.push_back(y);
else {
if (y.fi <= ans2.back().se) ans2.back().se = max(ans2.back().se, y.se);
else ans2.push_back(y);
}
}
int ans = 0;
for (auto y : ans2) ans += y.se - y.fi + 1;
cout << ans << "\n";
}
