Sorting is a common operation in many applications, and efficient algorithms to perform it have been developed. The most common uses of sorted sequences are: making lookup or search efficient; making merging of sequences efficient.
In this task the possible key values are the integers 1, 2 and 3. The required sorting order is non-decreasing. Sorting has to be accomplished by a sequence of exchange operations. An exchange operation, defined by two position numbers p and q, exchanges the elements in positions p and q.
You are given a sequence of key values. Write a program that computes the minimal number of exchange operations that are necessary to make the sequence sorted.

Input
The first line of input contains the number of records N (1≤ N ≤10⁵). Each of the following N lines contains a key value.

Output
Output the minimal number L of exchange operations needed to make the sequence sorted.

Sample input
9
2
2
1
3
3
3
2
3
1

Sample output
4