#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#define pb push_back
#define int long long
#define repp(i,x,n) for(int i=x;i<=n;i++)
#define rep(i,x,n) for(int i=x;i>=n;i--)
#define r0 return 0
#define fi first
#define se second
#define liow ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL)
#define jelek cout<<"jelek"<<endl
#define pii pair<int,int>
#define all(v) v.begin(),v.end()
#define tp tuple<int,int,int>
#define fl fflush(stdout)
#define ld long double
#pragma GCC optimize ("O2")
#pragma GCC optimize ("unroll-loops")
#define pil pair<int,int>
#define p3 pair<int,pii>
#define p5 pair<int,pair<pii,pii>>
using namespace std;
using namespace __gnu_pbds;
typedef tree<int,null_type,less<int>,rb_tree_tag,tree_order_statistics_node_update> ordered_set;
typedef tree<pair<int,int>, null_type, less<pair<int,int>>, rb_tree_tag, tree_order_statistics_node_update> ordered_multiset;
//const int mod=1e9+7;
const int SQMAX=635,INF=1e18;
const int mod=998244353;
//const int MOD=1e6+3;
mt19937_64 rng((unsigned int) chrono::steady_clock::now().time_since_epoch().count());
pii dr[8]={{-1,0},{-1,1},{0,1},{1,1},{1,0},{1,-1},{0,-1},{-1,-1}};
int dx[4]={1,0,-1,0};
int dy[4]={0,1,0,-1};
int dxx[4]={1,1,-1,-1};
int dyy[4]={1,-1,-1,1};
int mul(int x,int y){return (x%mod*y%mod)%mod;}
int expo(int b,int e){
if(e==0) return 1;
int tmp=expo(b,e/2);
if(e%2) return mul(tmp,mul(tmp,b));
else return mul(tmp,tmp);
}
const int maxn=100005;
const int N=1e5;
void solve(){
int L,N;cin>>L>>N;
vector<pii>seg;
repp(i,1,N){
int x;cin>>x;
int sum=0;
vector<int>v;
repp(j,1,x){
int y;cin>>y;
v.pb(y);
sum+=y;
}
int sisa=L-sum;
int nw=0;
int tot=0;
repp(i,0,x-1){
tot=sisa+v[i];
int lewat=v[i]-sisa;
int l=nw+1,r=nw+sisa+v[i];
if(lewat<=0){
nw+=v[i];
continue;
}
if(tot%2){
seg.pb({(l+r)/2-lewat/2,(l+r)/2+lewat/2});
} else {
seg.pb({(l+r)/2-lewat/2+1,(l+r)/2+lewat/2});
}
nw+=v[i];
}
}
if(seg.empty()){
cout<<0<<endl;
return;
}
sort(all(seg));
int ans=0;
repp(i,0,seg.size()-1){
int l=seg[i].fi;
int r=seg[i].se;
while(i+1<=seg.size()-1 && r>=seg[i+1].fi){
i++;
r=max(r,seg[i].se);
}
ans+=(r-l+1);
}
cout<<ans<<endl;
}
signed main(){
liow;
solve();
}
