# Python program to print odd Numbers in a List
# list of numbers
list1 = [10, 21, 4, 45, 66, 93]
# iterating each number in list
for num in list1:
# checking condition
if num % 2 != 0:
print(num, end = " ")
# Python program to print all ODD numbers in the range[a, b]
a, b = (7, 19)
for num in range(a, b+1): # b+1 is to include b itself
if num & 1:
print(num, end = ' ')
# output:
# 7 9 11 13 15 17 19
# Python program to print Even Numbers in given range
start, end = 0, 50
# iterating each number in list
for num in range(start, end + 1):
# checking condition
if num % 2 == 0:
print(num, end = " ")
for tc in range(int(input())):
a,b = map(int,input().split())
x = b//2 + (b%2)
y = a//2
print("Case %d: %d"%(tc+1,x*x-y*y))
"""
Input:
2
1 10
2 10
Output:
Case 1: 25
Case 2: 24
"""