When Bruce learned set theory, he assigned a homework question to his students.
Given a positive integer , find the number of subsets of the whole set that satisfies the following constraint: if an integer is in the subset, then the integers and are not in the subset. For example, given , the whole set is . The number of subsets satisfying the constraint is , including the empty set: , , , , , , , and .
Input Specification
The input will consist of one integer .
Output Specification
Output the number of subsets that satisfy the above constraints mod .
Sample Input
4
Sample Output
8
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