#include <bits/stdc++.h>
using namespace std;
struct segmentset {
set<pair<int, int>> s;
int ans() {
int ret = 0;
for(auto &[x, y]: s) ret += y - x + 1;
return ret;
}
void insert(int l, int r) {
if (s.size() == 0) {
s.insert({
l, r});
return;
}
auto a = s.lower_bound({
l, INT_MIN});
while (a != s.end() && r >= a->first) {
r = max(r, a->second);
s.erase(*a);
a = s.lower_bound({
l, INT_MIN});
}
while (a != s.begin()) {
a--;
if (l <= a->first) {
l = min(l, a->first);
s.erase(*a);
a = s.lower_bound({
l, INT_MIN});
}
else break;
}
s.insert({l, r});
}
};
int main() {
cin.tie(0)->sync_with_stdio(0);
int l, r;
cin >> l >> r;
segmentset s;
while (r--) {
int n;
cin >> n;
vector<int> a(n);
vector<int> ri(n);
vector<int> li(n);
for (auto &x : a) {
cin >> x;
}
int curi = 0;
for (int i = 0; i < n; i++) {
curi += a[i];
ri[i] = curi;
}
curi = l + 1;
for (int i = n-1; i >= 0; i--) {
curi -= a[i];
li[i] = curi;
}
for (int i = 0; i < n; i++) {
if(li[i] <= ri[i]) s.insert(li[i], ri[i]);
}
}
cout << s.ans() << '\n';
}
