Nested loops: print pattern - triangle of numbers

Problem: Print the following pattern for a given n (e.g. n=5 below).

    5

   454

  34543

 2345432

123454321

Solution in Python:

def print_pattern(n):

    """

    Author: Mayur P Srivastava

    n is number of colmns or rows.

    """

    for i in range(n):

        s = ""

        for j in range(i+1, n):

            s += " "

        for j in range(-i, i+1):

            s += str(n-abs(j))

        print s

Concepts learned: nested loops.