n,s = map(int,input().split())

ans = []
for i in range(1,n+1):
    if i <= s:
        ans.append(i)
        s -= i
    else:
        break

if s == 0:
    print(len(ans))
    print(*ans)
    exit()

now = len(ans)-1
l = len(ans)
while s:
    dif = n-ans[now]-(l-now-1)
    if dif >= s:
        ans[now] += s
        print(len(ans))
        print(*ans)
        exit()
    else:
        ans[now] += dif
        s -= dif
        now -= 1