Author: Divyanshu aka StellarCoder
Python 2.x
This series is the result of my love for PYTHON and now I want to share this love with all of you. I will introduce you to mystical and charismatic python.
Yeah! mystical and charismatic..
Don't you believe me??
Let me show you then...

To print in python

print 'Hello, World!'

Output --> Hello, World!

Comments

'''This is a comment.'''

# This is also a comment

hash is used for single line comment and triple quotes for multiple lines

To input an integer in python

n=input()

To input String

a=raw_input()

To create an empty array(list in python)

arr=[]

To assign a value to all elements of an array

Let us say you wanna make an array of size 10 with each element equal to 0 ie. same value to all

arr=[0]*10

output --> [0,0,0,0,0,0,0,0,0,0]

To add item in array(list)

arr.append(1)
arr.append(2)
print arr

output --> [1,2]

while loop syntax

i=0
l=10
while i<l:
    print i
    i=i+1

for-in loop syntax

arr=[1,2,3,4]

for item in arr:
    print item

#output will be each array item printed in separate line

you can use any thing instead of item like a,b,c it,key ie.literally anything except keywords and reserved words

To print print statements in same line, just add a comma after your text

print 'Next print statement after this will be printed in same line',
print "I'm in first line"

Output-->Next print statement after this will be printed in same line I'm in first line' 

Variant of for in loop.

If you want to loop from i=start to end let us say 1 to 10

for i in range(1,11):
    print i

in range(start,end)--> *start* is inclusive and end is exclusive**, read like this [start,end)

If you don't pass an argument, default value--> start = 0,end=len(string)

if you want to jump by n then range(start,end,jump=n), default value --> jump=0

To sort an array(both integer and string)

arr=[7,6,4,9,3,2,8,1,5]
arr1=sorted(arr)
arr2=sorted(arr,reverse=True)

# output arr1 --> [1,2,3,4,5,6,7,8,9]
#output arr2 --> [9,8,7,6,5,4,3,2,1]

NOTE --> In Python, when using true-false, remember to CAPITALIZE FIRST LETTER ie. *True and *False**

logical operators just type name in english ie. && --> and , || --> or , ! --> not
bitwise operators are same as C ie. & , | , ^(XOR)
all arithmetic operators are also same as in C

if-else in python

a=5

if a==5:
    print "Sweet Mother of Mercy!"

elif a==6:
    print "It's a SIX"

elif a==4:
    print "It's a FOUR"

else:
    print "Not an interesting number"

Output --> Sweet Mother of Mercy!

========Various types of Inputs========

If you have to input a variable

n=input()

If you have to input a character or string (including spaces)

a=raw_input()

If you want to store words in an array, for eg. if the line is --> save this line in an array

arr=map(str,raw_input().split())

output --> ['save','this','line','in','an','array']

If you want to store integers in an array for eg. --> 5 7 3 2 62 7 8

arr=map(int,raw_input().split())

#output --> [5,7,3,2,62,7,8]

If you want to input a line/word and store each character seperately eg.--> divyanshu

a=list(raw_input())

#output --> ['d','i','v','y','a','n','s','h','u']

To acces an particular index in array

print a[0]
print a[1]

ouput--> 'd'
output --> 'i' 

Suppose you input an integer as a string, now you want to convert it to integer use this

a='5'
a=int(a)

To convert an integer to string

b=5
b=str(5)

To join all items of an array

arr=['d','i','v','y','a','n','s','h','u']
c=''.join(arr)

output will be--> 'divyanshu'

To reverse an array or string

a='example'
arr=['d','i','v','y','a','n','s','h','u']
b=a[::-1]
arr=arr[::-1]

output --> 'elpmaxe'
similarly for array (feeling too tired to type ;-) )

That's it for now......
Next article will be posted soon....stay tuned !