Help me in solving LB01 problem

help
,
1

My issue

hint

My code

# Update the program below to solve the problem

t = int(input())            
for i in range(t):
    
    A, C = map(int, input().split())
   
    SUM = A+C
    B =SUM % 2
    if B == 0:
        print(B)
    else:
        print("-1")

Learning course: Logic Building in Python
Problem Link: CodeChef: Practical coding for everyone