Abc

for f in range(int(input())):
	a,b=input().split()
	print(f"Case #{f+1}: ",end="")
	a=list(a)
	b=list(b)
	c=len(a)
	d=len(b)
	e=min(c,d)
	a1=a if c>d else b
	a.reverse()
	b.reverse()
	l=[]
	c=0
	for i in range(e):
		s=(int(a[i])+int(b[i]))+c
		l.append(s%10)
		c=s//10
	for j in range(e,len(a1)):
		s2=int(a1[i])+c
		l.append(s2%10)
		c=s2//10
	if c>0:
		l.append(c)
	l.reverse()
	for k in l:
		print(k,end="")