a,b,c = map(int,input().split())
ans = []
if b >= c:
    if c % a == 0:
        ans.append(c//a)
if (b + c) % a == 0:
    ans.append((b+c)//a)
ans.sort()
if ans:
    for e in ans:
        print(e)
else:print(-1)