#include <bits/stdc++.h>
using ll = long long;
using namespace std;
int main() {
std::ios_base::sync_with_stdio(false);
std::cin.tie(nullptr);
ll n, rows;
cin >> n >> rows;
vector<pair<ll, ll>> a;
for (int i = 0; i < rows; i++) {
ll x;
cin >> x;
ll tot = 0;
vector<ll> block(x);
for (int j = 0; j < x; j++) {
cin >> block[j];
tot += block[j];
}
ll freespace = n - tot;
ll pref = 0;
for (int k = 0; k < x; k++) {
ll l = pref + freespace;
ll r = pref + block[k] - 1;
if (l <= r) {
a.push_back({l, r});
}
pref += block[k];
}
}
if (a.size() == 0) {
cout << 0 << "\n";
return 0;
}
sort(a.begin(), a.end());
ll ans = 0;
ll left = a[0].first;
ll right = a[0].second;
for (int i = 1; i < a.size(); i++) {
ll l = a[i].first;
ll r = a[i].second;
if (l > right + 1) {
ans += right - left + 1;
left = l;
right = r;
} else
right = max(right, r);
}
ans += right - left + 1;
cout << ans << "\n";
}
