1 #include<iostream>
 2 #include<cstdio>
 3 #include<algorithm>
 4 #include<cmath>
 5 #include<cstring>
 6 #include<set>
 7 #include<map>
 8 #include<queue>
 9 #include<vector>
10 //#define INF 0x3f3f3f3f
11 #define N 100005
12 typedef long long ll;
13 using namespace std;
14 struct node{
15     int x;
16     int y;
17 }a[N],b[N];
18 bool cmp(node aa,node bb){
19     if(aa.x==bb.x){
20         return aa.y<bb.y;
21     }
22     else
23         return aa.x<bb.x;
24 }
25 int main()
26 {
27     int t,n;
28     scanf("%d",&t);
29     int i,j;
30     while(t--)
31     {
32         scanf("%d",&n);
33         for(i=0;i<n;i++)
34             scanf("%d%d",&a[i].x,&a[i].y);
35         sort(a,a+n,cmp);
36         for(i=0;i<n;i++)
37             scanf("%d%d",&b[i].x,&b[i].y);
38         sort(b,b+n,cmp);
39         multiset<ll>st;
40         multiset<ll>::iterator it;
41         int ans=0;
42         st.clear();
43         j=0;
44         for(i=0;i<n;i++){
45             while(a[i].x>=b[j].x&&j<n){
46                     st.insert(b[j].y);
47                     j++;
48             }
49             if(st.empty())
50                 continue;
51             it=st.upper_bound(a[i].y);
52             if(it!=st.begin())
53             {
54                 it--;
55                 ans++;
56                 st.erase(it);
57             }
58         }
59         printf("%d\n",ans);
60     }
61 }