#include <iostream>
#include <sstream>
#include <iomanip>
#include <vector>
#include <string>
#include <map>
#include <set>
#include <algorithm>
#include <numeric>
#include <iterator>
#include <complex>
#include <queue>
#include <stack>
#include <cmath>
using namespace std;
typedef long long LL;

class SortingGame
{
public:
	int fewestMoves(vector<int> board, int k) 
	{
		vector<int> sorted(board);
		sort(sorted.begin(), sorted.end());

		vector< vector<int> > Q;
		set< vector<int> >    V;
		Q.push_back(board), V.insert(board);
		for(int N=0; !Q.empty(); ++N)
		{
			vector< vector<int> > Q2;
			for(int i=0; i<Q.size(); ++i)
			{
				vector<int>& b = Q[i];
				if( b == sorted )
					return N;
				for(int i=0; i+k<=b.size(); ++i)
				{
					reverse(b.begin()+i, b.begin()+i+k);
					if( !V.count(b) )
						Q2.push_back(b), V.insert(b);
					reverse(b.begin()+i, b.begin()+i+k);
				}
			}
			Q.swap(Q2);
		}
		return -1;
	}

// BEGIN CUT HERE
	public:
	void run_test(int Case) { if ((Case == -1) || (Case == 0)) test_case_0(); if ((Case == -1) || (Case == 1)) test_case_1(); if ((Case == -1) || (Case == 2)) test_case_2(); if ((Case == -1) || (Case == 3)) test_case_3(); if ((Case == -1) || (Case == 4)) test_case_4(); }
	private:
	template <typename T> string print_array(const vector<T> &V) { ostringstream os; os << "{ "; for (typename vector<T>::const_iterator iter = V.begin(); iter != V.end(); ++iter) os << '\"' << *iter << "\","; os << " }"; return os.str(); }
	void verify_case(int Case, const int &Expected, const int &Received) { cerr << "Test Case #" << Case << "..."; if (Expected == Received) cerr << "PASSED" << endl; else { cerr << "FAILED" << endl; cerr << "\tExpected: \"" << Expected << '\"' << endl; cerr << "\tReceived: \"" << Received << '\"' << endl; } }
	void test_case_0() { int Arr0[] = {1,2,3}; vector <int> Arg0(Arr0, Arr0 + (sizeof(Arr0) / sizeof(Arr0[0]))); int Arg1 = 3; int Arg2 = 0; verify_case(0, Arg2, fewestMoves(Arg0, Arg1)); }
	void test_case_1() { int Arr0[] = {3,2,1}; vector <int> Arg0(Arr0, Arr0 + (sizeof(Arr0) / sizeof(Arr0[0]))); int Arg1 = 3; int Arg2 = 1; verify_case(1, Arg2, fewestMoves(Arg0, Arg1)); }
	void test_case_2() { int Arr0[] = {5,4,3,2,1}; vector <int> Arg0(Arr0, Arr0 + (sizeof(Arr0) / sizeof(Arr0[0]))); int Arg1 = 2; int Arg2 = 10; verify_case(2, Arg2, fewestMoves(Arg0, Arg1)); }
	void test_case_3() { int Arr0[] = {3,2,4,1,5}; vector <int> Arg0(Arr0, Arr0 + (sizeof(Arr0) / sizeof(Arr0[0]))); int Arg1 = 4; int Arg2 = -1; verify_case(3, Arg2, fewestMoves(Arg0, Arg1)); }
	void test_case_4() { int Arr0[] = {7,2,1,6,8,4,3,5}; vector <int> Arg0(Arr0, Arr0 + (sizeof(Arr0) / sizeof(Arr0[0]))); int Arg1 = 4; int Arg2 = 7; verify_case(4, Arg2, fewestMoves(Arg0, Arg1)); }

// END CUT HERE
};
// BEGIN CUT HERE 
int main() {
	SortingGame().run_test(-1);
}
// END CUT HERE
