🚀 Python Crash Course (CIITM Dhanbad 4th Sem) — From Zero to Exam Ready

❗ Didn’t study all semester?
This guide is built to take you from zero → confident pass → top score using only what matters in exams.

🎯 HOW TO USE THIS (IMPORTANT)

• Read once slowly (Day 1)
• Revise 2 times (Day 2–3)
• Practice programs (Day 4)
• Final quick revision (Day 5)

👉 Focus on VVI ⭐⭐⭐⭐ topics

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🧠 UNIT I — PROGRAMMING FUNDAMENTALS

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✅ Problem Solving (VVI ⭐⭐⭐⭐)

Short Para:
Problem solving means understanding a problem and solving it step-by-step using logic before writing code.

🔹 Steps (Write Exactly in Exam)

1. Problem Definition → understand problem
2. Analysis → break into parts
3. Algorithm → steps of solution
4. Coding → write program
5. Testing → check errors
6. Maintenance → improve program

📌 Tip: Write 1 line per step → full marks

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✅ Algorithm

Short Para:
An algorithm is a step-by-step procedure to solve a problem in a finite number of steps.

Example:

1. Start  
2. Input A, B  
3. Sum = A + B  
4. Print Sum  
5. End  

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✅ Flowchart

Short Para:
A flowchart is a diagram that represents program logic using symbols like oval (start), rectangle (process), and diamond (decision).

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✅ Types of Errors (VVI ⭐⭐⭐⭐)

Short Para:
Errors are mistakes in a program that cause wrong output or failure.

• Syntax Error → wrong code
• Runtime Error → error during execution
• Logical Error → wrong result

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✅ Top-Down vs Bottom-Up

Short Para:
Top-down divides a big problem into smaller parts, while bottom-up combines small parts into a complete solution.

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✅ Debugging & Documentation

• Debugging → finding and fixing errors
• Documentation → writing program details

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🧠 UNIT II — PYTHON CORE

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✅ Python Basics

Short Para:
Python is a simple, high-level, interpreted language that executes code line by line.

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✅ Keywords & Identifiers

• Keywords → reserved words
• Identifiers → variable names

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✅ Data Types

• int → numbers
• float → decimal
• str → text
• bool → True/False

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✅ Operators (VVI ⭐⭐⭐⭐)

Short Para:
Operators are symbols used to perform operations on variables.

• Arithmetic → + - * /
• Relational → > < ==
• Logical → and or not
• Assignment → =
• Bitwise → & |
• Ternary → a if cond else b

⚠️ No ++ or -- in Python

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✅ Input / Output

x = input("Enter:")
print(x)

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✅ Control Statements

If-Else

if x > 0:
    print("Positive")
else:
    print("Negative")

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Loops

for i in range(5):
    print(i)

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✅ break vs continue vs pass (VVI ⭐⭐⭐⭐)

• break → stop loop
• continue → skip iteration
• pass → do nothing

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✅ Functions

Short Para:
Functions are reusable blocks of code used to perform tasks.

def add(a, b):
    return a + b

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✅ Recursion (VVI ⭐⭐⭐⭐)

Short Para:
Recursion is when a function calls itself.

Factorial Program

def fact(n):
    if n == 1:
        return 1
    return n * fact(n-1)

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✅ Exception Handling

try:
    x = 10/0
except:
    print("Error")

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🧠 UNIT III — STRINGS & LISTS

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✅ Strings

Short Para:
A string is a sequence of characters used to store text.

s = "Python"
print(len(s))

• Slicing → s[0:3]
• Traversal → loop
• find()

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✅ Lists (VVI ⭐⭐⭐⭐)

Short Para:
A list is a collection of values stored in one variable.

lst = [1,2,3]
lst.append(4)

• Access → lst[0]
• Delete → del lst[1]

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✅ 2D List

matrix = [[1,2],[3,4]]

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🧠 UNIT IV — OOP

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✅ Class & Object (VVI ⭐⭐⭐⭐)

Short Para:
A class is a blueprint, and an object is an instance of that class.

class Student:
    def __init__(self, name):
        self.name = name

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✅ Constructor

__init__() initializes object

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🧠 UNIT V — DATA STRUCTURES

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✅ Stack (LIFO)

stack = []
stack.append(1)
stack.pop()

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✅ Queue (FIFO)

from collections import deque
q = deque()
q.append(1)
q.popleft()

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🔍 SEARCHING (VVI ⭐⭐⭐⭐)

Linear Search

for i in arr:
    if i == x:
        print("Found")

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Binary Search (Concept)

Works on sorted data

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🔄 SORTING (VVI ⭐⭐⭐⭐)

Bubble Sort

for i in range(n):
    for j in range(n-i-1):
        if arr[j] > arr[j+1]:
            arr[j], arr[j+1] = arr[j+1], arr[j]

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🔥 MUST PREPARE (HIGH SCORE ZONE)

• Problem solving steps ⭐⭐⭐⭐
• Errors ⭐⭐⭐⭐
• Operators ⭐⭐⭐⭐
• break vs continue ⭐⭐⭐⭐
• Lists ⭐⭐⭐⭐
• Recursion ⭐⭐⭐⭐
• Stack vs Queue ⭐⭐⭐⭐
• Sorting ⭐⭐⭐⭐

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📅 5-DAY MASTER PLAN

Day 1 → Unit 1 + 2
Day 2 → Unit 2 complete
Day 3 → Unit 3 + 4
Day 4 → Programs
Day 5 → Revision

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🚀 FINAL MESSAGE

You don’t need months.
You need focus + repetition + smart topics.

👉 Revise this 2–3 times
👉 Practice key programs
👉 Walk into exam with confidence