Share a malignant sign-in question. 
Input:
2
0
1
,
Output:
1
0
Idea : Core:
90% of people who understand the question think that "()" is a sequence of palindrome brackets.
First, if it is a sequence of parentheses, then n must be an even number, and the parenthesis form is either ()() one group after another, or (()) matryoshka form, but both of these conform to the definition of palindrome.
So except for n==1, n is other numbers and the result is 0.