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);
            }
    }
}