#!/usr/bin/env python
# coding: utf-8

# # The Zen of Python

# In[1]:


import this


# # Variables

# A name that is used to denote something or a value is called a variable. In python, variables can be declared and values can be assigned to it as follows,

# In[2]:


x = 2
y = 5
xy = 'Hey'


# In[3]:


print(x + y, xy)


# Multiple variables can be assigned with the same value.

# In[4]:


x = y = 1


# In[5]:


print(x, y)


# # Operators

# ## Arithmetic Operators

# | Symbol | Task Performed |
# |----|---|
# | +  | Addition |
# | -  | Subtraction |
# | /  | division |
# | %  | mod (modulo)|
# | *  | multiplication |
# | //  | floor division |
# | **  | to the power of |

# In[6]:


1 + 2


# In[7]:


2 - 1


# In[8]:


1 * 2


# In[9]:


5 / 3


# `//` if floor division also referred to as integer division. The resultant value is a whole integer, though the result’s type is not necessarily int. The modulo operation `%` finds the remainder after division of one number by another (sometimes called modulus).

# In[10]:


5 // 3


# In[11]:


5 // 3.0


# In[12]:


a, b = 13, 3
b * (a // b) + (a % b)


# ## Relational Operators

# | Symbol | Task Performed |
# |----|---|
# | == | True, if it is equal |
# | !=  | True, if not equal to |
# | < | less than |
# | > | greater than |
# | <=  | less than or equal to |
# | >=  | greater than or equal to |

# In[13]:


z = 1


# In[14]:


z == 1


# In[15]:


z > 1


# ## Bitwise Operators

# | Symbol | Task Performed |
# |----|---|
# | &  | Logical And |
# | l  | Logical OR |
# | ^  | XOR |
# | ~  | Negate |
# | >>  | Right shift |
# | <<  | Left shift |

# In[16]:


a = 2 #0b10
b = 3 #0b11


# In[17]:


print(a & b)
print(bin(a & b))


# In[18]:


5 >> 1


# 0000 0101 -> 5 
# 
# Shifting the digits by 1 to the right and zero padding
# 
# 0000 0010 -> 2

# In[19]:


5 << 1


# 0000 0101 -> 5 
# 
# Shifting the digits by 1 to the left and zero padding
# 
# 0000 1010 -> 10

# # Built-in Functions

# Python comes loaded with pre-built functions

# ## Conversion from one system to another

# Conversion from hexadecimal to decimal is done by adding prefix **0x** to the hexadecimal value or vice versa by using built in **hex( )**, Octal to decimal by adding prefix **0o** to the octal value or vice versa by using built in function **oct( )**.

# In[20]:


hex(170)


# In[21]:


0xAA


# In[22]:


oct(8)


# In[23]:


0o10


# **int( )** accepts two values when used for conversion, one is the value in a different number system and the other is its base. Note that input number in the different number system should be of string type.

# In[24]:


print(int('0o10',8))
print(int('0xaa',16))
print(int('1010',2))


# **int( )** can also be used to get only the integer value of a float number or can be used to convert a number which is of type string to integer format. Similarly, the function **str( )** can be used to convert the integer back to string format

# In[25]:


print(int(7.7))
print(int('7'))


# Also note that function **bin( )** is used for binary and **float( )** for decimal/float values. **chr( )** is used for converting ASCII to its alphabet equivalent, **ord( )** is used for the other way round.

# In[26]:


chr(98)


# In[27]:


ord('b')


# ## Simplifying Arithmetic Operations

# **round( )** function rounds the input value to a specified number of places or to the nearest integer. 

# In[28]:


print(round(5.6231))
print(round(4.55892, 2))


# **complex( )** is used to define a complex number and **abs( )** outputs the absolute value of the same.

# In[29]:


c = complex('3+4j')
print(c, abs(c))


# **divmod(x,y)** outputs the quotient and the remainder in a tuple(you will be learning about it in the further chapters) in the format (quotient, remainder). 

# In[30]:


divmod(9,2)


# **isinstance( )** returns True, if the first argument is an instance of that class. Multiple classes can also be checked at once.

# In[31]:


print(isinstance(1, int))
print(isinstance(1.0,int))
print(isinstance(1.0,(int,float)))


# **pow(x,y,z)** can be used to find the power $x^y$ also the mod of the resulting value with the third specified number can be found i.e. : ($x^y$ % z).

# In[32]:


print(pow(3,3))
print(pow(3,3,5))


# **`range(start, stop, step)`** function outputs the integers of the specified range. It can also be used to generate a series by specifying the difference between the two numbers within a particular range. Function **`range`** generates an interator, which can be converted to a list using `list(...)`

# In[33]:


print(range(3), list(range(3)))
print(range(2,9), list(range(2,9)))
print(range(2,27,8), list(range(2,27,8)))


# ## Accepting User Inputs

# **input( )** accepts input and stores it as a string. Hence, if the user inputs a integer, the code should convert the string to an integer and then proceed.

# In[37]:


abc = input("Type something here and it will be stored in variable abc: ")


# In[38]:


type(abc)


# Note that **type( )** returns the format or the type of a variable or a number