#include<bits/stdc++.h>

using ll=long long;

struct Num{
    int l1,r1;
    int l2,r2;
};

#define MAXN 400005

int n;
Num num[MAXN];
int id[MAXN];
ll lcl,lcr;
ll mcl,mcr;
ll rcl,rcr;
int get(int x){
    return (x<0)?num[-x].l2:num[x].r2;
}
int pos[MAXN];
int m;
int ans;

void cntans(int val){
    if(lcr<rcl){
        ll sum=lcr+rcl+mcr;
        ll pos=(sum+1)/2;
        if(pos>lcr&&pos<=lcr+mcr) ans+=val;
    }else if(lcl>rcr){
        ll sum=lcl+rcr+mcr;
        ll pos=(sum+1)/2;
        if(pos>lcl&&pos<=lcl+mcr) ans+=val;
    }else if(mcr) ans+=val;

    return;
}

void run(){
    ans=0;
    lcl=lcr=mcl=mcr=rcl=rcr=0;
    std::cin>>n;
    for(int i=1;i<=n;i++){
        std::cin>>num[i].l1>>num[i].r1>>num[i].l2>>num[i].r2;
        rcl+=num[i].l1,rcr+=num[i].r1;
        id[2*i-1]=-i,id[2*i]=i;
        pos[2*i-1]=num[i].l2,pos[2*i]=num[i].r2;
    }
    m=2*n; std::sort(pos+1,pos+m+1);
    m=std::unique(pos+1,pos+m+1)-pos-1;
    std::sort(id+1,id+2*n+1,[](int x,int y){
        int xv=get(x),yv=get(y);
        if(xv!=yv) return xv<yv;
        else return x<y;
    });
    ans=0;
    int pn=1;
    for(int i=1;i<=m;i++){
        int pr=pn;
        while(pr<=2*n){
            if(get(id[pr])>pos[i]) break;
            ++pr;
        }
        for(int j=pn;j<pr;j++){
            if(id[j]<0){
                rcl-=num[-id[j]].l1,rcr-=num[-id[j]].r1;
                mcl+=num[-id[j]].l1,mcr+=num[-id[j]].r1;
            }
        }
        cntans(1);
        for(int j=pn;j<pr;j++){
            if(id[j]>0){
                mcl-=num[id[j]].l1,mcr-=num[id[j]].r1;
                lcl+=num[id[j]].l1,lcr+=num[id[j]].r1;
            }
        }     
        if(i!=m){
            cntans(pos[i+1]-pos[i]-1);
        }
        pn=pr;
    }
    std::cout<<ans<<'\n';
        
    return;
}

int c,T;
int main(){
    std::ios::sync_with_stdio(false);
    std::cin.tie(0),std::cout.tie(0);

    std::cin>>c>>T; for(int i=0;i<T;i++) run();

    return 0;
}