#include<bits/stdc++.h> using namespace std; const int N=1e5+10; int n,x; bool f[N]; struct point{ int s,e; }a[N]; bool cmp(point x,point y) { return x.e<y.e; } int main() { cin>>x; while(x--) { cin>>n; int ans=0; for(int i=1;i<=n;++i) { cin>>a[i].s>>a[i].e; } sort(a+1,a+n+1,cmp); for(int i=1;i<=n;++i) { bool f1=0; for(int j=a[i].s;j<=a[i].e;++j) { if(f[j]==1) { f1=1; break; } } if(!f1) { f[a[i].e]=1; ans++; } } cout<<ans<<'\n'; } return 0; }