/*
Author: Nguyen Chi Thanh - High School for the Gifted - VNU.HCM (i2528)
*/
#include <bits/stdc++.h>
using namespace std;
/* START OF TEMPALTE */
// #define int long long
#define ll long long
#define ull unsigned long long
#define ld long double
#define pii pair<int, int>
#define pll pair<ll, ll>
#define fi first
#define se second
#define __builtin_popcount __builtin_popcountll
#define all(x) (x).begin(), (x).end()
#define BIT(x, i) (((x) >> (i)) & 1)
#define MASK(x) (1ll << (x))
#define SZ(a) ((int32_t)a.size())
#define debug(a, l, r) {for (int _i = (l); _i <= (r); ++_i) cout << (a)[_i] << ' '; cout << '\n';}
template<class X, class Y>
bool minimize(X &x, const Y &y) {
if (x > y) {
x = y;
return true;
} else return false;
}
template<class X, class Y>
bool maximize(X &x, const Y &y) {
if (x < y) {
x = y;
return true;
} else return false;
}
/* END OF TEMPALTE */
int len, n;
void solve() {
cin >> len >> n;
vector<int> lens;
vector<pii> segs;
for (int i = 1; i <= n; ++i) {
int x; cin >> x;
int sumwidth = 0;
lens.clear();
for (int j = 0; j < x; ++j) {
int width; cin >> width;
sumwidth += width;
lens.push_back(width);
}
int shift = len - sumwidth;
int sumpre = 0;
for (int j = 0; j < x; ++j) {
int l = sumpre + shift + 1;
int r = sumpre + lens[j];
if (l <= r)
segs.push_back({l, r});
sumpre += lens[j];
}
}
int res = 0;
if (!segs.empty()) {
sort(all(segs));
int l = segs[0].fi, r = segs[0].se;
for (int i = 1; i < SZ(segs); ++i) {
int nxt_l = segs[i].fi;
int nxt_r = segs[i].se;
if (nxt_l > r + 1) {
res += (r - l + 1);
l = nxt_l;
r = nxt_r;
} else maximize(r, nxt_r);
}
res += r - l + 1;
}
cout << res;
}
signed main() {
#ifdef NCTHANH
freopen("input.txt", "r", stdin);
freopen("output.txt", "w", stdout);
#endif
ios_base::sync_with_stdio(0);
cin.tie(nullptr); cout.tie(nullptr);
solve();
return 0;
}
