import java.util.*;
public class uva10783 {
public static void main(String [] args) {
Scanner scn = new Scanner(System.in);
int n = scn.nextInt();
for(int x=0;x<n;x++) {
int a = scn.nextInt();
int b = scn.nextInt();
int total = 0;
for(int y=a;y<=b;y++) {
if((y%2)!=0)
total += y;
}
System.out.println("Case "+(x+1) +": " +total);
}
}
}