#read the dimension of the grid dim = in_file. readline() dim = dim. strip() dim = int(dim) # create an empty grid grid = [] # populate the grid for i in range (dim): line = in_file. readline() line = line. strip() row = line. split() for j in range (dim): row[j] = int (row[j]) grid. append (row) # close the file in_file. close() # get the number of paths in the grid and print num_paths = count_paths (dim, 0, 0) print ('number of paths in a grid of dimension', dim, 'is', num_paths) print () # get the maximum path sum and print max_path_sum = path_sum (grid, dim, 0, 0) print ('greatest path sum is', max_path_sum)