#include <iostream>

#include <string>

#include <cstring>

#include <cstdlib>

#include <cstdio>

#include <cmath>

#include <algorithm>

#include <stack>

#include <queue>

#include <cctype>

#include <vector>

#include <iterator>

#include <set>

#include <map>

#include <sstream>

using namespace std;

#define mem(a,b) memset(a,b,sizeof(a))

#define pf printf

#define sf scanf

#define spf sprintf

#define pb push_back

#define debug printf("!\n")

#define MAXN 100000 + 10

#define MAX(a,b) a>b?a:b

#define blank pf("\n")

#define LL long long

#define ALL(x) x.begin(),x.end()

#define INS(x) inserter(x,x.begin())

#define pqueue priority_queue

#define INF 0x3f3f3f3f

int n,m;

struct node

{

    int h,w;

}a[],b[];

bool cmp(node x,node y)

{

    return x.h < y.h;

}

multiset<int> mt;

multiset<int>::iterator it;

int main()

{

    int i,j;

    int t;

    sf("%d",&t);

    while(t--)

    {

        sf("%d",&n);

        for(i=;i<=n;i++)

        {

            sf("%d%d",&a[i].h,&a[i].w);

        }

        for(i=;i<=n;i++)

        {

            sf("%d%d",&b[i].h,&b[i].w);

        }

        sort(a+,a+n+,cmp);

        sort(b+,b+n+,cmp);

        mt.clear();

        int cnt=;

        for(i=,j=;i<=n;i++)

        {

            while(j<=n && a[i].h>=b[j].h)

            {

                mt.insert(b[j].w);

                j++;

            }

            if(mt.empty()) continue;

            it = mt.upper_bound(a[i].w);

            if(it!=mt.begin()) it--;

            if((*it) <= a[i].w)

            {

                cnt++;

                mt.erase(it);

            }

        }

        pf("%d\n",cnt);

    }

    return ;

}