Anthony is obsessed with sorting algorithms. After mastering a couple different sorting algorithms, he is now learning how to solve more unconventional sorting problems. Initially, there is an array of size . Anthony can perform the following operation any number of times: change an element of to any arbitrarily large non-negative integer. Let the array be the prefix bitwise XOR array of . Formally, . Please tell Anthony the minimum number of operations to sort in non-decreasing order.
Constraints
Subtask 1 [20%]
Subtask 2 [80%]
No additional constraints.
Input Specification
The first line contains the integer .
The next line contains space-separated integers, representing the array .
Output Specification
Output the minimum number of operations to make nondecreasing.
Sample Input
3
2 2 4
Sample Output
1
Explanation for Sample
operation can be performed by changing the first element to , making nondecreasing.
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