#include<bits/stdc++.h>
using namespace std;
#define int long long

const int N = 2e5+10;
int c, T;

int n;
struct L{
	int l1, r1, l2, r2;
}x[N];

struct K{
	int l, r;
};

vector<K> ad[N<<1];
vector<K> de[N<<1];

int cnt[N];
bool isk[N];

void check(){
	int sum = 0, sum2 = 0;
	for(int i = 1; i <= 4; i++) sum += cnt[i];
	for(int i = 1; i <= 4; i++){
		sum2 += cnt[i];
		if(sum2 >= ((sum+1)>>1)){
			isk[i] = 1;
			return;
		}
	}
}

void dfs(int pos){
	if(pos == n+1){
		check();
		return;
	}
	for(int i = x[pos].l1; i <= x[pos].r1; i++)
		for(int j = x[pos].l2; j <= x[pos].r2; j++){
			cnt[j] += i;
			dfs(pos+1);
			cnt[j] -= i;
		}
}

void solvebf(){
	dfs(1);
	int cnt = 0;
	for(int i = 1; i <= 4; i++){
		if(isk[i]) cnt++;
		isk[i] = 0;
	}
	cout << cnt << endl;
}

void solve(){
	int b[N<<1], l1 = 0, l2 = 0, l3 = 0, r1 = 0, r2 = 0, r3 = 0, ans = 0;
	for(int i = 1; i <= n; i++){
		b[i*2-1] = x[i].l2;
		x[i].r2++;
		b[i*2] = x[i].r2;
		l3 += x[i].l1;
		r3 += x[i].r1;
	}
	sort(b+1,b+n*2+1);
	for(int i = 1; i <= n; i++){
		x[i].l2 = lower_bound(b+1,b+n*2+1,x[i].l2)-b;
		x[i].r2 = lower_bound(b+1,b+n*2+1,x[i].r2)-b;
		ad[x[i].l2].push_back((K){x[i].l1,x[i].r1});
		de[x[i].r2].push_back((K){x[i].l1,x[i].r1});
	}
	for(int i = 1; i <= 2*n; i++){
		for(auto x : ad[i])
			l3 -= x.l, r3 -= x.r, l2 += x.l, r2 += x.r;
		for(auto x : de[i])
			l2 -= x.l, r2 -= x.r, l1 += x.l, r1 += x.r;
		ad[i].clear();
		de[i].clear();
		if(r2 == 0) continue;
		if(r1 <= l3){
			int sum = (r1 + l3 + r2);
			if((sum+1) / 2 > r1 && (sum+1) / 2 <= r1 + r2)
				ans += b[i+1]-b[i];
		} else if(r3 <= l1){
			int sum = (r3 + l1 + r2);
			if((sum+1) / 2 > l1 && (sum+1) / 2 <= l1 + r2)
				ans += b[i+1]-b[i];
		} else {
			ans += b[i+1]-b[i];
		}
	}
	cout << ans << "\n";
}

signed main(){
	freopen("lucky.in","r",stdin);
	freopen("lucky.out","w",stdout);
	cin >> c >> T;
	while(T--){
	cin >> n;
	for(int i = 1; i <= n; i++)
		cin >> x[i].l1 >> x[i].r1 >> x[i].l2 >> x[i].r2;
	solve();
	continue;
	if(c <= 2){
		solvebf();
		continue;
	}
	solve();
	}
	
	return 0;
}