Python Input and Output Exercise

Whether you’re building interactive command-line applications, processing user data, or working with files, a solid understanding of Python’s input and output mechanisms is crucial.

• Input: how a program receives data
• Output: how it presents results.

This article serves as a practical guide to enhancing your skills in this essential area.

Through a series of 15 coding questions on basic I/O operations, you’ll practice and solidify your understanding of taking user input, displaying information effectively, and interacting with files.

Furthermore, you’ll be able to practice various techniques for formatting output to present data in a clear and user-friendly manner.

Let us know if you have any alternative solutions. Your insights will help other developers.

Use Online Code Editor to solve exercise questions.

Exercise 1: Accept Numbers From User

Write a program to accept two integer numbers from the user and calculate their product.

Help: Take user input in Python

num1 = int(input("Enter first number "))
num2 = int(input("Enter second number "))

res = num1 * num2
print("Multiplication:", res)Code language: Python (python)

Exercise 2: Format Output String

Write a program to display four string “My, “Name“, “Is“, “James” as “My**Name**Is**James“.

Use the print() function to format the given words in the specified format. Display the ** separator between each string.

Given:

str1 = 'My'
str2 = 'Name'
str3 = 'Is'
str4 = 'James'Code language: Python (python)

Expected Output:

For example: print('your code') should display My**Name**Is**James

str1 = 'My'
str2 = 'Name'
str3 = 'Is'
str4 = 'James'
print(str1, str2, str3, str4, sep='**')Code language: Python (python)

Exercise 3: Display Decimal Number to Octal using print() function

Given:

num = 8Code language: Python (python)

Expected Output:

The octal representation of the decimal number 8 is 10.

num = 8
print('%o' % num)Code language: Python (python)

Exercise 4: Display Float Number with 2 Decimal Places

Given:

num = 458.541315Code language: Python (python)

Expected Output:

458.54

num = 458.541315
print('%.2f' % num)Code language: Python (python)

Exercise 5: Accept a list of 5 float numbers as an input from the user

Refer:

• Take list as a input in Python.
• Python list

Expected Output:

[78.6, 78.6, 85.3, 1.2, 3.5]

numbers = []

# 5 is the list size
# run loop 5 times
for i in range(0, 5):
    print("Enter number at location", i, ":")
    # accept float number from user
    item = float(input())
    # add it to the list
    numbers.append(item)

print("User List:", numbers)Code language: Python (python)

Exercise 6: Write all content of a file into a new file by skipping line number 5

See:

• Python file handling
• Python Read file
• Python write file

Create a test.txt file and add the below content to it.

line1
line2
line3
line4
line5
line6
line7

line1
line2
line3
line4
line6
line7

# read test.txt
with open("test.txt", "r") as fp:
    # read all lines from a file
    lines = fp.readlines()

# open new file in write mode
with open("new_file.txt", "w") as fp:
    count = 0
    # iterate each lines from a test.txt
    for line in lines:
        # skip 5th lines
        if count == 4:
            count += 1
            continue
        else:
            # write current line
            fp.write(line)
        # in each iteration reduce the count
        count += 1Code language: Python (python)

Exercise 7: Accept any three string from one input() call

Write a program to take three names as input from the user in a single call to the input() function.

See: Get multiple inputs from a user in one line

Expected Output

Enter three string Emma Jessa Kelly
Name1: Emma
Name2: Jessa
Name3: Kelly

str1, str2, str3 = input("Enter three string").split()
print('Name1:', str1)
print('Name2:', str2)
print('Name3:', str3)Code language: Python (python)

Exercise 8: Format variables using string.format() method

Write a program to use the string.format() method to format the following three variables according to the expected output.

Given:

totalMoney = 1000
quantity = 3
price = 450Code language: Python (python)

Expected Output:

I have 1000 dollars so I can buy 3 football for 450.00 dollars.

quantity = 3
totalMoney = 1000
price = 450
statement1 = "I have {1} dollars so I can buy {0} football for {2:.2f} dollars."
print(statement1.format(quantity, totalMoney, price))Code language: Python (python)

Exercise 9: Check File is Empty or Not

Write a program to check if the given file is empty or not

import os

size = os.stat("test.txt").st_size
if size == 0:
    print('file is empty')Code language: Python (python)

Exercise 10: Read Line Number 4 from File

See:

• Read Specific Lines From a File in Python
• Python read file

Create a test.txt file and add the below content to it.

test.txt file:

line1
line2
line3
line4
line5
line6
line7

# read file
with open("test.txt", "r") as fp:
    # read all lines from a file
    lines = fp.readlines()
    # get line number 3
    print(lines[2])Code language: Python (python)

Exercise 11: Percentage Display

Ask the user for a numerator and a denominator. Calculate the percentage and display it with two decimal places followed by a percent sign (e.g., 75.50%).

try:
    numerator = float(input("Enter the numerator: "))
    denominator = float(input("Enter the denominator: "))
    if denominator == 0:
        print("Error: Denominator cannot be zero.")
    else:
        percentage = (numerator / denominator) * 100
        print(f"The percentage is: {percentage:.2f}%")
except ValueError:
    print("Invalid input. Please enter numbers.")Code language: Python (python)

Exercise 12: Interactive Menu

Create a simple interactive menu with options like “1. Say Hello”, “2. Calculate Square”, “3. Exit”. Based on the user’s input, perform the corresponding action

while True:
    print("\nMenu:")
    print("1. Say Hello")
    print("2. Calculate Square")
    print("3. Exit")

    choice = input("Enter your choice (1-3): ")

    if choice == '1':
        print("Hello there!")
    elif choice == '2':
        try:
            number = int(input("Enter a number: "))
            square = number ** 2
            print(f"The square of {number} is {square}")
        except ValueError:
            print("Invalid input. Please enter an integer.")
    elif choice == '3':
        print("Exiting...")
        break
    else:
        print("Invalid choice. Please enter a number between 1 and 3.")Code language: Python (python)

Exercise 13: Display Right-Aligned Output

Ask the user for a word and a number. Print the word right-aligned in a field of width 20, followed by the number.

Expected Output:

Enter a word:  PYnative
Enter a number:  29
            PYnative29

word = input("Enter a word: ")
number = input("Enter a number: ")
print(f"{word:>20}{number}")Code language: Python (python)

Exercise 14: Tabular Output from Lists

You have two lists: names = ["Alice", "Bob", "Charlie"] and scores = [85, 92, 78]. Print these lists as a simple table with columns “Name” and “Score”.

Expected Output:

Name       Score
---------------
Alice      85   
Bob        92   
Charlie    78   

names = ["Alice", "Bob", "Charlie"]
scores = [85, 92, 78]

print(f"{'Name':<10} {'Score':<5}")
print("-" * 15)
for name, score in zip(names, scores):
    print(f"{name:<10} {score:<5}")Code language: Python (python)

Exercise 15: Padding with Zeros

Ask the user for a number. Print this number padded with leading zeros to a width of 5.

For example, if the input is 12, the output should be “00012“

number_str = input("Enter a number: ")
padded_number = number_str.zfill(5)
print(padded_number)Code language: Python (python)