#include <bits/stdc++.h>
using namespace std;
#define int long long
int m,n,p_now,ans;
vector <pair <int,int>> vec;
bool cmp(pair <int,int> x,pair <int,int> y){
if(x.first!=y.first) return x.first<y.first;
else return x.second>y.second;
}
signed main()
{
ios::sync_with_stdio(0);
cin.tie(0);
cin >> m >> n;
for(int i=1;i<=n;i++){
int c,sum=0;
cin >> c;
vector <int> v;
for(int j=1;j<=c;j++){
int x;
cin >> x;
v.push_back(x);
sum+=x;
}
int mov=(m-sum),qs=0;
for(int j=0;j<c;j++){
if(mov>=v[j]) continue;
int r=qs+v[j],l=qs+mov+1;
vec.push_back({l,r});
qs+=v[j];
}
}
sort(vec.begin(),vec.end(),cmp);
for(auto [x,y]:vec){
//cout << x << " " << y << "\n";
ans+=max(0LL,min(y-p_now+1,y-x+1));
p_now=max(p_now,y);
}
cout << ans;
}
