a,b=(int(x) for x in input().split())
if b % a == 0:
    print(a+b)
else:
    print(b-a) int(x) for x in input().split() for x in input().split() x input().split() ().split () input split for x in input().split() int(x) int x a,b=(int(x) for x in input().split()) a (int(x) for x in input().split()) b if b % a == 0:
    print(a+b)
else:
    print(b-a) b % a == 0 b % a b a 0 print(a+b) print a+b a b print(b-a) print b-a b a b=(int(x) for x in input().split()) (int(x) for x in input().split()) b a,b=(int(x) for x in input().split()) (int(x) for x in input().split()) a
a,b=(int(x) for x in input().split())
if b % a == 0:
    print(a+b)
else:
    print(b-a)