USER INPUT
Programs interactive tab bante hain jab user se input le sakein � CLI tools, forms, games sab input pe depend karte hain. input() function se user ka data lete hain aur uspe kaam karte hain.
Ye lesson kyun zaroori hai?
Har real-world program ko kisi na kisi se data chahiye � chahe woh calculator ho, login form ho, ya game. input() se aap user se puch sakte ho aur unka jawab le sakte ho.
Basic Input
input() function user se text leta hai aur return karta hai. Isme ek prompt message daal sakte ho jo user ko dikhega.
# Basic input
name = input("Aapka naam: ")
print(f"Hello, {name}!")input() se text input milta hai. User kuch type karega aur Enter dabayega.
Input hamesha string hota hai. Number chahiye to int() ya float() se convert karna padta hai.
Input validate karna zaroori hai � galat data aaye to error handle karo ya dobara pucho.
Number Input with Validation
Input hamesha string aata hai. Agar number chahiye to int() ya float() se convert karo. Agar user ne galat daala to ValueError aata hai � use try/except se handle karo.
# Number input with validation
while True:
try:
age = int(input("Aapki age: "))
if age > 0:
break
print("Age positive honi chahiye!")
except ValueError:
print("Sirf number daalo!")
print(f"Aap {age} saal ke hain.")Ye while True loop tab tak chalega jab tak valid number na mile. try/except se ValueError handle hota hai aur if age > 0 se negative values reject hoti hain.
Multiple Inputs
Ek line mein comma-separated values le sakte ho aur .split() se list mein convert kar sakte ho.
# Multiple inputs
data = input("Comma se values daalo: ").split(",")
print("Aapne daala:", data)
# Numbers ka list banana
nums = input("Numbers daalo (space se): ").split()
numbers = [int(x) for x in nums]
print(f"Sum: {sum(numbers)}")Input ke tips
- Input ke prompt mein space ya colon do �
"Name: "type karo,"Name"mat likho. - Validation ke liye
while True+try/except+breakka pattern use karo. .strip()se extra spaces hat jayenge �input("Name: ").strip().- Multiple inputs ke liye
.split()use karo � comma, space, ya kisi bhi delimiter se.
Quick check
input() use karke user se naam lo aur greet karo. Pehle input() se naam lo, phir print() se "Hello" ke saath naam dikhao.
Ek line mein input() se naam lo, doosri line mein print() se dikhao.
Common mistakes
age = input("Age: ")� ye string return karta hai,int()se convert karo agar number chahiye.- Validation ke bina
int(input())laga doge to galat input pe program crash hoga. .split()ke baad values strings hoti hain �int()yafloat()se convert karo agar number chahiye.- Prompt message mat bhoolo � bina prompt ke user ko samajh nahi aayega kya daalna hai.