#include <iostream> 

using namespace std;

int main(){

int t,a,b;

cin>>t;

for(int i=1;i<=t;i++){

cin>>a>>b;

int sum=0;

for(int j=a;j<=b;j++)if(j%2==1)sum+=j;

cout<<"Case "<<i<<": "<<sum<<endl;

}

}