📝 Strings

String kya hai?

name = "Python"
print(name[0])    # P
print(name[-1])   # n
print(name[0:3])  # Pyt
print(name[::-1]) # nohtyP (ulta)

String Methods

s = "Hello Python!"
print(s.upper())      # HELLO PYTHON!
print(s.lower())      # hello python!
print(s.replace("Python","Hindi")) # Hello Hindi!
print(s.find("Python")) # 6
print(len(s))         # 13
print(s.split(" "))   # ['Hello', 'Python!']

f-String

name = "Rahul"
age  = 20
print(f"Naam: {name}")
print(f"Umar: {age} saal")
print(f"5 x 7 = {5*7}")
pi = 3.14159
print(f"Pi = {pi:.2f}")   # 2 decimal

Strings — Practical Examples

# Chapter 3: Strings — Advanced Practice
print("=== Strings Practice ===")

# Example 1: Basic usage
result = "Python mein Strings bahut powerful hai!"
print(result)

# Example 2: Real world use
data = ["Strings", "Python", "Hindi", "PythonHindi.in"]
for item in data:
    print(f"Item: {item}")

print("\nPractice complete! Great job! 🎉")

Strings ke Important Concepts

• split() — Strings mein important concept
• join() — Strings mein important concept
• replace() — Strings mein important concept
• find() — Strings mein important concept
• strip() — Strings mein important concept
• upper()/lower() — Strings mein important concept

Common Mistakes — Dhyan Rakho!

Practice Exercises — Khud Try Karo!

1. Is chapter ke sab code examples khud type karo — copy-paste mat karo!
2. Har example mein kuch changes karo aur dekho kya hota hai
3. Ek chhota program banao jo is chapter ke concepts use kare
4. Apne dost ya family member ko explain karo yeh concept — teaching se best practice hoti hai
5. HackerRank ya LeetCode par is topic ke easy problems solve karo

Real World mein Strings ka Use

Summary aur Next Steps

Interview Mein Pooche Jane Wale Sawal

Aur Seekho — Resources

Python Career Guide 2026

Chapter 3 — Deep Practice aur Mastery

# Chapter 3: Strings — Advanced Examples
# Yeh code copy karo aur run karo!

# Example 1: Basic concept
print("=== Chapter 3: Strings ===")

# Example 2: List operations
items = ["Python", "Hindi", "Code", "Practice"]
for i, item in enumerate(items, 1):
    print(f"{i}. {item}")

# Example 3: Dictionary usage
chapter_info = {
    "number": 3,
    "title":  "Strings",
    "level":  "Beginner",
    "done":   False
}
for key, value in chapter_info.items():
    print(f"  {key:10}: {value}")

# Example 4: Function
def practice_summary(chapter, completed=False):
    status = "Complete ✅" if completed else "In Progress ⏳"
    return f"Chapter {chapter}: {status}"

print(practice_summary(3))
print(practice_summary(3, True))

Python Community aur Help Kaise Lein

Chapter 3 — Final Quiz aur Revision

📝 Chapter Summary

🧠 Is Chapter ke Important Concepts

💡 Pro Tips — Dhyan Rakho!

• String immutable hai — change karne par naya string banta hai
• Negative index: s[-1] = last character
• f-string use karo — format() se behtar hai
• strip() whitespace hatata hai — useful for user input
• 'in' operator se check karo: 'py' in 'python'

🏋️ Practice Karo — Khud Try Karo!

1. Apna naam store karo aur upar/neeche case print karo
2. String ko reverse karo slicing se
3. Email se username nikalo split('@') se
4. Sentence mein words count karo split() se
5. f-string mein calculation karo: f'{5*7}'

❓ Aksar Pooche Jane Wale Sawal

📚 Strings — Real World mein Kahan Use Hota Hai?

🎯 Is Chapter ko Master Karne ke Liye