Python Coding challenge - Day 844| What is the output of the following Python Code?

 

Code Explanation:

1. Defining the Class

class Check:

A class named Check is created.

It will contain a method that checks if a number is even.

2. Defining the Method

def even(self, n):

    return n if n % 2 == 0 else 0

even() is an instance method that takes one argument n.

It uses a conditional expression (ternary operator):

If n % 2 == 0 → number is even → return n.

Otherwise → return 0.

In simple terms:

Even number → returns itself

Odd number → returns 0

3. Creating an Object

c = Check()

Creates an instance c of the Check class.

This object can now call the even() method.

4. Initializing a Variable

s = 0

A variable s is set to 0.

It will be used to accumulate the sum of even numbers.

5. Loop from 1 to 5

for i in range(1, 6):

    s += c.even(i)

The loop runs for i = 1, 2, 3, 4, 5.

Each time, it calls c.even(i) and adds the result to s.

Let’s trace it step-by-step:

Iteration i c.even(i) Calculation s after iteration

1 1 0 (odd) 0 + 0 0

2 2 2 (even) 0 + 2 2

3 3 0 (odd) 2 + 0 2

4 4 4 (even) 2 + 4 6

5 5 0 (odd) 6 + 0 6

6. Printing the Result

print(s)

Prints the final accumulated value of s.

After the loop, s = 6.

Final Output

6

400 Days Python Coding Challenges with Explanation

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Python Coding challenge - Day 846| What is the output of the following Python Code?

 

Code Explanation:

1. Defining the Class

class Word:

Creates a class named Word.

This class can contain methods to perform operations on words or strings.

2. Defining a Method

def vowels(self, word):

Defines a method named vowels inside the Word class.

self refers to the instance of the class calling the method.

word is the string parameter for which we want to count vowels.

3. Initializing a Counter

count = 0

Initializes a variable count to 0.

This variable will keep track of the number of vowels found in the word.

4. Looping Through Each Character

for ch in word:

Iterates over each character ch in the input string word.

5. Checking if Character is a Vowel

if ch.lower() in "aeiou":

    count += 1

ch.lower() converts the character to lowercase, so the check is case-insensitive.

If the character is in "aeiou" → it is a vowel → increment count by 1.

Let’s trace for "Object":

Character ch.lower() Vowel? count after step

O                   o                   Yes        1

b                   b                    No        1

j                         j                    No        1

e                   e                    Yes        2

c                   c                    No        2

t                   t                    No        2

6. Returning the Count

return count

Returns the total number of vowels found in the word.

7. Creating an Object

w = Word()

Creates an instance w of the Word class.

This object can now call the vowels() method.

8. Calling the Method and Printing

print(w.vowels("Object"))

Calls the vowels() method on the object w with "Object" as input.

Returns 2 → number of vowels (O and e).

print() displays the result.

Final Output

2

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Python Coding challenge - Day 845| What is the output of the following Python Code?

Code Explanation:

1. Defining the Class

class Math:

This line defines a class called Math.

A class is a blueprint for creating objects.

All methods related to mathematical operations can go inside this class.

2. Defining the Method

def fact(self, n):

Defines a method called fact to calculate the factorial of a number n.

self refers to the instance of the class that will call this method.

3. Initializing the Result Variable

res = 1

Initializes a variable res to 1.

This variable will store the factorial as it is computed in the loop.

4. Loop to Compute Factorial

for i in range(1, n+1):

    res *= i

range(1, n+1) generates numbers from 1 to n inclusive.

On each iteration, res *= i multiplies the current value of res by i.

Let’s trace it for n = 4:

Iteration i res calculation res after iteration

1 1 1 * 1 1

2 2 1 * 2 2

3 3 2 * 3 6

4 4 6 * 4 24

5. Returning the Result

return res

After the loop, res holds the factorial of n.

return res sends this value back to the caller.

6. Creating an Object

m = Math()

Creates an instance m of the class Math.

This object can now access the fact method.

7. Calling the Method and Printing

print(m.fact(4))

Calls fact(4) on object m.

Computes 4! = 1*2*3*4 = 24.

print() outputs the result to the console.

Final Output

24

500 Days Python Coding Challenges with Explanation

 

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Python Coding Challenge - Question with Answer (01141125)

 

Explanation:

1. Class Declaration

class Counter:

This line defines a class named Counter.

2. Class Variable (Shared Across All Calls)

    x = 1

This is a class variable, not tied to any object.

Its value is shared every time the method is called.

Initial value: 1

3. Method Without self

    def nxt():

        Counter.x *= 2

        return Counter.x

Explanation:

def nxt(): → This method does not use self because we are not creating objects.

Counter.x *= 2 → Every time the method is called, the value of x is doubled.

return Counter.x → The updated value is returned.

4. Loop That Calls the Method Several Times

for _ in range(4):

This loop runs 4 times.

5. Printing the Result Each Time

    print(Counter.nxt(), end=" ")

Each loop iteration calls Counter.nxt()

The returned value is printed

end=" " keeps everything on one line with spaces

Final Output

2 4 8 16

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Python Coding challenge - Day 843| What is the output of the following Python Code?

 

Code Explanation:

1. Defining the Class

class A:

A new class named A is created.

This acts as a blueprint for creating objects (instances).

2. Declaring a Class Variable

count = 0

count is a class variable, shared by all objects of class A.

It belongs to the class itself, not to individual instances.

Initially, A.count = 0.

3. Defining the Constructor

def __init__(self):

    A.count += 1

__init__ is the constructor, called automatically every time an object of class A is created.

Each time an object is created, this line increases A.count by 1.

So it counts how many objects have been created.

4. Loop to Create Multiple Objects

for i in range(3):

    a = A()

The loop runs 3 times (i = 0, 1, 2).

Each time, a new object a of class A is created, and the constructor runs.

Let’s trace it:

Iteration Action A.count value

1st (i=0) new A() created 1

2nd (i=1) new A() created 2

3rd (i=2) new A() created 3

After the loop ends, A.count = 3.

The variable a refers to the last object created in the loop.

5. Printing the Count

print(a.count)

Here, we access count through the instance a, but since count is a class variable, Python looks it up in the class (A.count).

The value is 3.

Final Output

3

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10 Python One-Liners That Will Blow Your Mind

 

1 Reverse a string

text="Python"
print(text[::-1])

#source code --> clcoding.com 

Output:

nohtyP


2 Swap two vairables without a temp variable

a,b=5,20
a,b=b,a
print(a,b)

#source code --> clcoding.com 

Output:
20 5

3. check the string is palindrome

word="madam"
print(word==word[: :-1])

#source code --> clcoding.com 

Output:
True

4. Count Frequency of each element in a list

from collections import Counter
print(Counter(['a','b','c','b','a']))

#source code --> clcoding.com 
Output:
Counter({'a': 2, 'b': 2, 'c': 1})

5. Get all even numbers from a list

nums=[1,2,3,4,5,6,7,8]
print([n for n in nums if n%2==0])

#source code --> clcoding.com 
Output:
[2, 4, 6, 8]


6. Flatten a nested list

nested=[[1,2],[3,4],[5,6]]
print([x for sub in nested for x in sub])

#source code --> clcoding.com 
Output:
[1, 2, 3, 4, 5, 6]

7. Find the factorial of a number

import math
print(math.factorial(5))

#source code --> clcoding.com 
Output:
120

8. Find common elements between two list

a=[1,2,4,5,4]
b=[3,4,5,1,2]
print(list(set(a)& set(b)))

#source code --> clcoding.com 
Output:
[1, 2, 4, 5]

10. one liner FizzBuzz

print(['Fizz'*(i%3==0)+'Buzz'*(i%5==0) or i for i in range(1,16)])

#source code --> clcoding.com 
Output:
[1, 2, 'Fizz', 4, 'Buzz', 'Fizz', 7, 8, 'Fizz', 'Buzz', 11, 'Fizz', 13, 14, 'FizzBuzz']

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7 Lesser-Known Pandas Functions That’ll Blow Your Mind

1. explode()=Turns list items into rows

import pandas as pd

df = pd.DataFrame({"Name": ["A", "B"], 
                   "Tags": [["x", "y"], ["p", "q"]]})
df.explode("Tags")

#source code --> clcoding.com

Output:

Name
Tags
0
A
x
0
A
y
1
B
p
1
B
q

2. query()- Filter rows using expression

df = pd.DataFrame({"Age":[20,25,30], "Score":[90,85,70]})
df.query("Age > 22 and Score > 80")

#source code --> clcoding.com
Output:
Age
Score
1
25
85
3. nlargets()- Get the top n rows

df=pd.DataFrame({"Name":["A","B","C"],"Marks":[50,95,80]})
df.nlargest(1,"Marks")
#source code --> clcoding.com
Output:
Name
Marks
1
B
95
4. nsmallest()- Get the lowest n rows

df=pd.DataFrame({"A":[10,3,7],"B":[4,9,1]})
df.nsmallest(2,"A")
#source code --> clcoding.com
Output:
A
B
1
3
9
2
7
1


5. pivot_table()- Create summary table automatically

df=pd.DataFrame({
    "City":["A","A","B","B"],
    "Sales": [10,20,30,5]
})
df.pivot_table(values="Sales",index="City",aggfunc="sum")

#source code --> clcoding.com
Output:
Sales
City
A
30
B
35
6. fillna(method="ffill")- Fills missing values forward

df = pd.DataFrame({"X":[1,None,None,4]})
df.fillna(method="ffill")

#source code --> clcoding.com
Output:
X
0
1.0
1
1.0
2
1.0
3
4.0
7. assign()- Adds new column cleanly

df = pd.DataFrame({"A":[1,2,3]})
df = df.assign(B=df.A * 10)
print(df)

#source code --> clcoding.com
Output:
   A   B
0  1  10
1  2  20
2  3  30

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Python Coding Challenge - Question with Answer (01131125)

 

Explanation:

Create a List

nums = [2, 4, 6]

A list named nums is created with three integer elements: 2, 4, and 6.

This will be used to calculate the average of its elements later.

Initialize Loop Control Variables

i = 0

s = 0

i → Acts as a loop counter, starting from 0.

s → A sum accumulator initialized to 0.

It will store the running total of the numbers in the list.

Start the While Loop

while i < len(nums):

The loop runs as long as i is less than the length of the list nums.

Since len(nums) is 3, this means the loop will run while i = 0, 1, 2.

This ensures every element in the list is processed once.

Add the Current Element to the Sum

    s += nums[i]

At each loop iteration:

The element at index i is accessed: nums[i].

It is added to the sum s.

Example of how s changes:

When i=0: s = 0 + 2 = 2

When i=1: s = 2 + 4 = 6

When i=2: s = 6 + 6 = 12

Increment the Loop Counter

    i += 1

After processing one element, i increases by 1.

This moves to the next element of the list in the next iteration.

Print the Final Result

print(s // len(nums))

Once the loop ends, the total sum s is 12.

The expression s // len(nums) performs integer division:

12 // 3 = 4

Hence, it prints the average (integer form) of the list elements.

Final Output

4

Probability and Statistics using Python

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