#include <bits/stdc++.h>
using namespace std;
int N,s,e;
const int MaxN=3e4;
struct LINE{
int s,e;
LINE(int s=0, int e=0):s(s),e(e){}
}line[MaxN];
bool comp(LINE lhs, LINE rhs){
return lhs.s<rhs.s;
}
int main() {
int ans=0,case_=1;
while(cin>>N){
for(int n=0;n<N;n++){
cin>>s>>e;
line[n].s=s;
line[n].e=e;
}
sort(line,line+N,comp);
for(int n=0;n<N;n++)
for(int m=n+1;m<N;m++){
if(line[n].e>line[m].s)
ans++;
}
int total=(N*(N-1))/2;
cout<<"Case "<<case_<<": "<<total-ans<<"\n";
case_++;
}
return 0;
}
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