Python Basics — Day 4(Input & Output in Python)

Day 4 — Input & Output in Python

01. Output with print()

The print() function displays values on the screen.
When printing multiple values separated by commas, Python automatically adds spaces.

print("Hello")
print("Age:", 25, "years")  
# Output: Age: 25 years

02. Input with input()

The input() function receives user input as a string (str).

name = input("Enter your name: ")
print("Hello,", name)

👉 Note: The result of input() is always a string.
To use numbers, you must convert the type.

age = int(input("Enter your age: "))  # str → int
print("Next year you will be", age + 1)

03.f-strings (Formatted Strings)

An elegant way to include variables inside a string.
Add an f before the string and wrap variables inside {}.

name = "Sabin"
age = 35
print(f"My name is {name}, and I am {age} years old.")

📌 You can also format numbers:

pi = 3.141592
print(f"Pi rounded to 2 decimals: {pi:.2f}")   # 3.14

04. Multi-line Strings

Use triple quotes """ """ or ''' ''' to print multiple lines.

msg = """Starting Python study!
Today we are learning about input and output.
"""
print(msg)

05.Practice Examples

Example 1: Input + Output

food = input("What is your favorite food? ")
print("Your favorite food is", food, "!")

Example 2: f-string

name = input("Enter your name: ")
age = int(input("Enter your age: "))
print(f"{name}, you are {age} years old. Next year you will be {age+1}.")

Example 3: Floating-point Formatting

num = 3.14159
print(f"One decimal place: {num:.1f}")
print(f"Three decimal places: {num:.3f}")