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

typedef long long LL ;
const int N = 2e5+100 ;

int id , T ;
int n ;
struct nn
{
	int la , ra , lb , rb ;
}p[N] ;
int yy[N<<1] , R , c[N<<1] ;
vector<int> ve1[N<<1] , ve2[N<<1] ;
void solve()
{
	scanf("%d" , &n ) ;
	for(int i = 1 ; i <= n ; i ++ ) {
		scanf("%d%d%d%d" , &p[i].la , &p[i].ra , &p[i].lb , &p[i].rb ) ;
		p[i].rb ++ ;
		yy[++R] = p[i].lb , yy[++R] = p[i].rb ;
	}
	sort(yy+1,yy+R+1) ; R = unique(yy+1,yy+R+1) - (yy+1) ; 
	LL lMin = 0 , lMax = 0 , rMin = 0 , rMax = 0 , sum = 0 ;
	for(int i = 1 ; i <= n ; i ++ ) {
		p[i].lb = lower_bound(yy+1,yy+R+1,p[i].lb) - yy ;
		p[i].rb = lower_bound(yy+1,yy+R+1,p[i].rb) - yy ;
		c[p[i].lb] ++ , c[p[i].rb] -- ;
		ve1[p[i].lb].push_back(i) ; 
		ve2[p[i].rb].push_back(i) ;
		rMin += p[i].la , rMax += p[i].ra ;
	}
	LL ans = 0 ;
	for(int i = 1 ; i <= R ; i ++ ) {
		c[i] += c[i-1] ;
		for(int id : ve1[i] ) {
			rMin -= p[id].la , rMax -= p[id].ra ;
			sum += p[id].ra ;
		}
		for(int id : ve2[i] ) {
			lMin += p[id].la , lMax += p[id].ra ;
			sum -= p[id].ra ;
		}
		if( c[i] ) {
			LL ll = max(lMin,rMin) , rr = min(lMax,rMax) ;
			if( ll <= rr ) ans += yy[i+1]-yy[i] ;
			else if( lMax < rMin ) {
				if( ll-rr <= sum ) {
					ans += yy[i+1]-yy[i] ;
				}
			}
			else if( ll-rr+1 <= sum ) {
				ans += yy[i+1]-yy[i] ;
			}
		}
	}
	printf("%lld\n" , ans ) ;
	for(int i = 1 ; i <= R ; i ++ ) {
		c[i] = 0 ; ve1[i].clear() ; ve2[i].clear() ; 
	}
	R = 0 ;
}

int main()
{
	freopen("lucky.in","r",stdin) ; 
	freopen("lucky.out","w",stdout) ;
	scanf("%d%d" , &id , &T ) ;
	while( T -- ) solve() ;
	return 0 ;
}