Day 1

Module 1

Syllabus

Basic coding skills
- Working with data types, ✅ 2025-09-03
- Keywords, ✅ 2025-09-03
- Variables and Operators, ✅ 2025-09-03
working with numeric data,
- Type conversions, ✅ 2025-09-03
- Input, Processing, ✅ 2025-09-03
- and Output, Formatting output.
Data Types
- String,
- Numeric(int, float, complex),
- Bool,
- List,
- Tuple,
- Dict,
- Set and Frozen Set
Control statements
Selection structure (if-else),
Iteration structure (for, while)
type assertion
Implicit type conversion
Explicit type conversion (type conver)

# 1
print("Hi Arun CS")

# 2
print("Hey Sneha")

Her Question

Implicit Type Conversion

Casting is done automatically

x = 5      # int
y = 2.5    # float
z = x + y  # int + float
print(z)   # 7.5
print(type(z))  # <class 'float'>

Explicit Type Conversion

Casting is done by us

a = "42"
b = int(a)     # converting string to int
c = float(b)   # converting int to float
d = str(c)     # converting float back to string

print(a, type(a))  # "42" <class 'str'>
print(b, type(b))  # 42   <class 'int'>
print(c, type(c))  # 42.0 <class 'float'>
print(d, type(d))  # "42.0" <class 'str'>

Keywords

Python keywords are reserved words that have special meanings and purposes within the Python language

Keywords

Keyword	Description
and	A logical operator
as	To create an alias
assert	For debugging
break	To break out of a loop
class	To define a class
continue	To continue to the next iteration of a loop
def	To define a function
del	To delete an object
elif	Used in conditional statements, same as else if
else	Used in conditional statements
except	Used with exceptions, what to do when an exception occurs
False	Boolean value, result of comparison operations
finally	Used with exceptions, a block of code that will be executed no matter if there is an exception or not
for	To create a for loop
from	To import specific parts of a module
global	To declare a global variable
if	To make a conditional statement
import	To import a module
in	To check if a value is present in a list, tuple, etc.
is	To test if two variables are equal
lambda	To create an anonymous function
None	Represents a null value
nonlocal	To declare a non-local variable
not	A logical operator
or	A logical operator
pass	A null statement, a statement that will do nothing
raise	To raise an exception
return	To exit a function and return a value
True	Boolean value, result of comparison operations
try	To make a try...except statement
while	To create a while loop
with	Used to simplify exception handling
yield	To return a list of values from a generator

Datatypes

# 3 
print(type(2))
print(type(2.0))
print(type(""))

output

<class 'int'>
<class 'float'>
<class 'str'>

Variables

A variable in Python is like a little label you stick onto a piece of data so you can refer to it later
Eg:
Consider , there is a program in which you have to use 13232132131 this number , its like everywhere in the program

something = 13232132131 / 2
anotherthing = something * 13232132131

sure you can copy paste it but checkout this version

number = 13232132131
something = number /2 
anotherthing = something * number

its like giving it a suitable name , so that you can use it by name rather than remembering its value.

Operators

Arithmetic

Arithmetic Operators

a , b  = 1 , 2 
a + b  # 3 "#" is the single line comment
a - b  # -1  
a * b  # 2 
a / b  # .5 
a % b  #  1 
b ** 2 # 4
a // b # 0

Comparison Operator

a, b = 5, 10

# Equal to
a == b  # False

# Not equal to
a != b  # True

# Greater than
a > b   # False

# Less than
a < b   # True

# Greater than or equal to
a >= b  # False

# Less than or equal to
a <= b  # True

Logical Operators

x, y = True, False

# AND - True if both operands are True
x and y  # False

# OR - True if at least one operand is True
x or y   # True

# NOT - Inverts the Boolean value 0 -> 1 , 1 -> 0
not x    # False
not y    # True

Membership Operators

lst = [1, 2, 3, 4]
name = "Arun"

# IN - True if value is found in sequence
2 in lst       # True
"run" in name  # True
5 in lst       # False

# NOT IN - True if value is not found in sequence
5 not in lst   # True
"y" not in name # True

Identity Operators

m = [1, 2]
n = [1, 2]
p = m

# IS - True if both variables point to same object
m is p    # True

m is n    # False (same values but different objects)

# IS NOT - True if variables point to different objects
m is not n  # True

print(m is n) # False , different objects even if values are sae
print(m == n) # True same value even if different objects

Bitwise Operators

a , b = 1, 2  # 01 , 10

''' Bitwise AND 
  01
& 10 '''
a & b  # 0

#Bitwise OR
# 11 
a | b  # 3

# Bitwise XOR
 
a ^ b  # 3

# Bitwise NOT
# this might be confusing explain later.
~a     # -2

#  Left Shift (<<)

a << 1  # 2

#Right Shift (>>)
a >> 1  # 0

explain biwise not 🏁 delete

Assignment Operators

x = 10

x += 3  # x = x + 3 → 13
x -= 2  # 11
x *= 2  #  22
x /= 4  # 5.5
x %= 3  #  2.5
x **= 2 #   6.25
x //= 2 #  3.0

Type Casting

int(3.1) # 3 
float(3) # 3.0
str(10) # '10'

a = 5 
type(a)
a = str(a)
type(a)
a = float(a)
type(a)

Input , output , processing

# input
a = input("Enter a number")

# output
print(a)

One thing to note here that the default type will be a string from the input() and you may need to type cast it to work as expected for example

a = input("Enter a number")
if a==5:
	print("HI")

this program will not work as expected (run and find out) (happens because int(5) is not same as str(5))

a = int(input("Enter a number"))
if a==5:
	print("HI")