Spiralna matrica reda n

'''
Spiralna matrica, npr: za n = 3:
1 2 3
8 9 4
7 6 5
'''

a = [[0 for x in xrange(30)] for x in xrange(30)]

n = int(raw_input(" Unesite red matrice: "))
print ""

s = 1
for i in range(n):
    for j in range(i, n-i):
        a[i][j] = s
        s = s + 1

    for j in range(i+1, n-i):
        a[j][n-i-1] = s
        s = s + 1

    for j in range(n-i-2, i-1, -1):
        a[n-i-1][j] = s
        s = s + 1

    for j in range(n-i-2, i, -1):
        a[j][i] = s
        s = s + 1

# STAMPANJE MATRICE
for i in range(n):
    for j in range(n):
        if a[i][j] > 9:
            print str(a[i][j]) + " ",
        else:
            print " " + str(a[i][j]) + " ",
    print ""

input()