Sets

Set ek unordered collection hai jiska ek hi defining rule hai: usme har value unique hoti hai. Duplicate add karo to kuch nahi hota — woh pehle se hi wahan hai.

numbers = {1, 2, 3, 2, 1}
print(numbers)

numbers.add(4)
print(numbers)

a = {1, 2, 3}
b = {2, 3, 4}
print(a | b)
print(a & b)
print(a - b)

{1, 2, 3}
{1, 2, 3, 4}
{1, 2, 3, 4}
{2, 3}
{1}

• {1, 2, 3, 2, 1} bante hi {1, 2, 3} mein collapse ho jaata hai — duplicates bach hi nahi paate
• | union hai — dono sets mein jo bhi hai sab kuch
• & intersection hai — sirf woh jo dono mein hai
• - difference hai — jo pehle set mein hai lekin doosre mein nahi

Yeh genuinely useful hain, sirf ek novelty nahi: list ko deduplicate karna bas list(set(my_list)) jitna simple hai, aur do collections overlap kar rahe hain ya nahi yeh check karna sirf ek & door hai.

Aage: conditional statements — apne code ko actually ek value ke basis par branch karwana.