LeastSumPath-81

#!/usr/bin/python
# Project Euler, problem 81
# Note: statement of the problem appears ambiguous
# By: A.O.

import sys
import math

def main(argv):

  try:
    size = 80
    matrix = {}

    # Load in data, convert to integers
    row = 0
    for line in sys.stdin:
      matrix[row] = [int(val) for val in (line.rstrip("\n").split(","))]
      row += 1

    #print matrix

    for row in range(size):
      for col in range(size):
        # Nothing to check
        if (row == 0 and col == 0):
          pass

        # Can only check to the left
        elif (row == 0 and col > 0):
          matrix[row][col] += matrix[row][col - 1]

        # Can only check above
        elif (col == 0 and row > 0):
          matrix[row][col] += matrix[row - 1][col]

        # See which of the paths, from above or left is less
        else:
          if (matrix[row-1][col] < matrix[row][col - 1]):
            matrix[row][col] += matrix[row-1][col]
          else:
            matrix[row][col] += matrix[row][col - 1]

    print "Shortest path = %d" % matrix[79][79]


  except "end of file":
      return None

if __name__ == "__main__":
  main(sys.argv)