spiral_numbers.py

#!/usr/bin/env python
#
#Find the pattern and complete the function: 
#int[][] spiral(int n);
#where n is the size of the 2D array.
#Sample Result
#input = 3
#123
#894
#765
#
#input = 4
#01 02 03 04
#12 13 14 05
#11 16 15 06
#10 09 08 07
#
#input = 8
#1 2 3 4 5 6 7 8
#28 29 30 31 32 33 34 9
#27 48 49 50 51 52 35 10
#26 47 60 61 62 53 36 11
#25 46 59 64 63 54 37 12
#24 45 58 57 56 55 38 13
#23 44 43 42 41 40 39 14
#22 21 20 19 18 17 16 15
def fillSquare(size, startValue, startRow, startCol, outputSquare):

    for column in range(startCol, startCol + size):
        outputSquare[startRow][column] = startValue
        startValue += 1
    for row in range(startRow + 1, startRow + size):
        outputSquare[row][startCol + size -1] = startValue
        startValue += 1
    for column in reversed(range(startCol, startCol + size - 1)):
        outputSquare[startRow + size - 1][column] = startValue
        startValue += 1
    for row in reversed(range(startRow + 1, startRow + size - 1)):
        outputSquare[row][startCol] = startValue
        startValue += 1
    

    if(size - 2 >= 0):
        fillSquare(size-2, startValue, startRow + 1, startCol + 1,     outputSquare)
        

def main():
    size = input("input size of the spiral:")
    if size < 0:
        print "Sorry can only print squares of size > 0"
        return
    
    outputSquare = [[0]*size for i in range(size)]
    
    fillSquare(size, 1, 0, 0, outputSquare)
    
    for row in outputSquare:
        print row
    
    print "spiral of size %d is as follows:" % size
    
if __name__ == "__main__":
    main()