Dapangmao dapangmao

Python's string object is immutable. An extra space has to be used to lower alphanumeric characters and squeeze others.
- Time O(n); Space O(n)

#-------------------------------------------------------------------------------
# Name:        Valid Palindrome
# Purpose:
#
#            Given a string, determine if it is a palindrome, considering only
#            alphanumeric characters and ignoring cases.

One example of test-driven development in Python

Function or method is the most basic unit in Python programming. Test-driven development is a key for a developer to assure the code quality of those units. In his book, Harry Percival illustrated a few great examples about how to use TDD with Python and Django. It seems that for web development, TDD including unit testing and integration testing is the cornerstone for every success. For data analysis, coding mostly relies on built-in packages instead large framework like Django, which makes TDD easier. In my opnion, TDD in data analysis could have three steps.

Step 1: requirement analysis

Before writing any code for data analysis, the programmer should seriously ask the customer or himself about the requirements.
- What are the input parameter?
what if the input data doesn't fit the assumptions?

http://www.codeskulptor.org/#user26_ZvPjz7GLuE8FuyP.py

# Mini-project #6 - Blackjack

import simplegui
import random

# load card sprite - 949x392 - source: jfitz.com
CARD_SIZE = (73, 98)

Recursive method

def binary_search(A, target):
    return _binary_search(A, target, 0, len(A) - 1)
    
def _binary_search(A, target, lo, hi):
    if lo > hi:
        return -1
    mid = (lo + hi) / 2
 if A[mid] == target:

The class to create tree

class TreeNode:
    def __init__(self, val):
        self.left = None
        self.right = None
        self.val = val

def to_root(input):
    a = [TreeNode(i) if i != '#' else None for i in input]

	# Test-driven development in Python for data analysis

	import doctest, sys
	def maxProduct(A):
	""" A function to find the maximum value for a continuous subarray.
	:param A: an array or list
	:type A: lst

	- testcase1
	>>> maxProduct([0, 2, 3,-2,4, 1, -1])

	import sqlite3
	import glob
	import sas7bdat

	class SASexport(sas7bdat.SAS7BDAT):
	def head(self, n=5):
	for i, row in enumerate(self.readData()):
	print row
	if i == n:
	break

	#
	# Implementation of the CHAR compression algorithm which corresponds to the literal "SASYZCRL".


	def decompressCHAR(offset, page):
	length = len(page)
	resultByteArray = []
	currentResultArrayIndex = 0
	for currentByteIndex in range(length):
	controlByte = page[offset+currentByteIndex] & 0xF0

	from doctest import testmod
	import math

	def factorial(n):
	"""Return the factorial of n, an exact integer >= 0.

	If the result is small enough to fit in an int, return an int.
	Else return a long.

	>>> [factorial(n) for n in range(6)]

	"""Convert to and from Roman numerals"""

	#-------------------------------------------------------------------------------
	#
	# http://woodpecker.org.cn/diveintopython/unit_testing/stage_1.html
	#
	#-------------------------------------------------------------------------------

	import re