1 #include <stdio.h>
 2 #include <iostream>
 3 #include <algorithm>
 4 using namespace std;
 5 
 6 struct Node
 7 {
 8     int l,w;
 9 }node[5005],setup[5005];
10 
11 bool cmp(Node a,Node b)
12 {
13     if (a.l==b.l)
14         return a.w<b.w;
15     return a.l<b.l;
16 }
17 
18 int main()
19 {
20     int t;
21     cin>>t;
22     while (t--)
23     {
24         int n;
25         int i,j;
26         cin>>n;
27         for (i=0;i<n;i++)
28         {
29             cin>>node[i].l>>node[i].w;
30         }
31         sort(node,node+n,cmp);
32         int ans=1;
33         setup[0].l=node[0].l;
34         setup[0].w=node[0].w;
35 
36         for (i=1;i<n;i++)
37         {
38             int ok=0;
39             for (j=0;j<ans;j++)
40             {
41                 if (setup[j].l<=node[i].l&&setup[j].w<=node[i].w)
42                 {
43                     setup[j].l=node[i].l;
44                     setup[j].w=node[i].w;
45                     ok=1;
46                     break;
47                 }
48             }
49             if (ok==0)
50             {
51                 setup[ans].l=node[i].l;
52                 setup[ans].w=node[i].w;
53                 ans++;
54             }
55         }
56         cout<<ans<<endl;
57     }
58     return 0;
59 }