""" Purpose: demonstrate nested loop abilities
    Problem: Get an integer n from the user and then print an n-by-n
       grid of one-digit numbers, whose rows are numbered 0 to n-1
       and columns are numbered 0 to n-1, wwhere the digit in the
       r-th row, c-th column is the the last digit of the product r x c
"""

# get dimension of the digit box
reply = input( "Enter integer: " )
n = int( reply )

# print an n-by-n grid one row at a time.
for r in range( 0, n ) :
    # handle printing of the row r entries for the digit box -- need to loop
    # through the n columns one by one
    #    -  each time through calculate a value and print it.
    #    -  the value is last digit of product r * c, where r is current row
    #       and c is the current column
    ...

    # finish processing the printing of the row
    ...