import sys

class mergesort():

    def merge_sort(self, A, p, r):

        if p < r:

            q = (p + r) / 2

            self.merge_sort(A, p, q)

            self.merge_sort(A, q+1, r)

            self.merge(A, p, q, r)

            return A

    def merge(self, A, p, q, r):

        n1 = q - p + 1

        n2 = r - q

        L = [0 for i in range(n1+1)]

        R = [0 for i in range(n2+1)]

        for i in range(n1):

            L[i] = A[p+i]

        for j in range(n2):

            R[j] = A[q+j+1]

        L[n1] = sys.maxint

        R[n2] = sys.maxint

        i = 0; j = 0

        for k in range(p, r):

            if L[i] <= R[j]:

                A[k] = L[i]

                i += 1

            else:

                A[k] = R[j]

                j += 1

sort = mergesort()

A = [1,3,5,7,9,2,4,6,8,10]

print sort.merge_sort(A, 0, len(A)-1)