DEV Community: Keerti Sadana S

PYTHON - LIST TASK 2

Keerti Sadana S — Fri, 25 Sep 2026 18:45:41 +0000

1) Find max, second max from a given list

l1 = [100,28,46,78]
max = l1[0]
for i in l1:
    if i > max:
        max = i
print(max)
l1 = [28,46,78,100]
max = l1[0]
second_max = 0
for i in l1:
    if i >= max:
        second_max = max
        max = i
print(second_max)

Output:
100
78

2) Find min, second min from a given list

l1 = [100,28,46,78]
min = l1[0]
for i in l1:
    if i <= min:
        min = i
print(min)
l1 = [100,46,78,28]
min = l1[0]
second_min = 0
for i in l1:
    if i <= min:
        second_min = min
        min = i
print(second_min)

Output:
28
46

3) Reverse a list without using reverse()

l1 = [100,28,48,69]
rev = []
i = len(l1)-1
while i>=0:
    rev.append(l1[i])
    i-=1
print(rev)

Output:
[69, 48, 28, 100]

4) Confirm if a given list is palindrome or not:

l1 = [10,20,30,20,10]
l2 = l1[::-1]
print(l1==l2)

Output:
True

5) Remove duplicate elements from a list:

l1 = [10,20,30,20,10]
l2 = []
for i in l1:
    if i not in l2:
        l2.append(i)
print(l2)

Output:
[10,20,30]

PYTHON - REVERSE(),SORT(),COPY() AND COUNT()

Keerti Sadana S — Fri, 25 Sep 2026 18:04:44 +0000

Python List Reverse():
-> The reverse() method is a built-in method in Python that reverses the order of elements in a list.
-> This method modifies the original list and does not return a new list, which makes it an efficient way to perform the reversal without unnecessary memory uses.

a = [1, 2, 3, 4, 1, 2, 6] 
a.reverse() 
print(a)

Output:
[6, 2, 1, 4, 3, 2, 1]

Sort():
-> The sort() method in Python is used to arrange the elements of a list in a specific order.
-> It works only on lists, modifies the original list in place, and does not return a new list.

a = [5, 3, 8, 1, 2]
a.sort()
print(a)

Output:
[1, 2, 3, 5, 8]

sort vs sorted:
sort --> in-place sorting: The original list gets modified.
sorted --> returns a new list with elements sorted.

Copy():
-> The copy() method in Python is used to create a shallow copy of a list.
-> This means that the method creates a new list containing the same elements as the original list but maintains its own identity in memory.
-> It's useful when you want to ensure that changes to the new list do not affect the original list and vice versa.

a = [1, 2, 3]
b = a.copy()
print('a:', a)
print('b:', b)

Output:
a: [1, 2, 3]
b: [1, 2, 3]

Count():
-> The count() method in Python returns the number of times a specified substring appears in a string.
-> It is commonly used in string analysis to quickly check how often certain characters or words appear.

s = "hello world"
res = s.count("o")
print(res)
s = "hello world"
res = s.count("o")
print(res)

Output:
2

PYTHON - DEL(), REMOVE() AND POP()

Keerti Sadana S — Fri, 25 Sep 2026 17:23:03 +0000

del():
-> del is a Python keyword used to delete items from a list by index or to remove the entire list.
-> With del, we can specify a single element by index or use slicing to delete a range of elements.

a = [1, 2, 3, 2, 3, 4, 5]
del a[3]
print(a)
a = [1, 2, 3, 2, 3, 4, 5]
del a[1:3]
print(a)

Output:
[1, 2, 3, 3, 4, 5]
[1, 2, 3, 4, 5]

remove():
The remove() method removes the first matching value from the list. It requires the value we want to remove from list as its argument.

a = [1, 2, 3, 2, 3, 4, 5]
a.remove(3)
print(a)

Output:
[1, 2, 2, 3, 4, 5]

pop():
-> The pop() method removes and returns an element from the list.
-> By default, it removes the last element, but we can specify an index to remove an element at a particular position.

a = [1, 2, 3, 2, 3, 4, 5]
a.pop(3)
print(a)

Output:
[1, 2, 3, 3, 4, 5]

del() VS remove() vs pop():

PYTHON - LIST TASK

Keerti Sadana S — Mon, 21 Sep 2026 17:16:36 +0000

1) Print q, h, a marks in separate lines

q = [90,87,65,67,89]
h = [96,97,95,69,99]
a = [99,98,100,76,49]

marks = [q,h,a]
i = 0
while i<len(marks):
    print(marks[i])
    i+=1

Output:
[90, 87, 65, 67, 89]
[96, 97, 95, 69, 99]
[99, 98, 100, 76, 49]

2) Calculate the total and Percentage of q, h and a

q = [90,87,65,67,89]
h = [96,97,95,69,99]
a = [99,98,100,76,49]
mark = [q,h,a]
no = len(mark[0])
k = 1
for i in mark:
    total = 0
    for j in i:
        total+=j
    print(f'Total of sublist {k} = {total}')
    print(f'Percent of sublist {k} = {(total*100)//(no*100)}%')
    k+=1

3) Calculate Average of Tamil (first subject)

q = [90,87,65,67,89]
h = [96,97,95,69,99]
a = [99,98,100,76,49]
mark = [q,h,a]
total = 0
for i in mark:
    total += i[0]
print(f'Average of Tamil = {total/len(mark)}')

Output:
Average of Tamil = 95.0

4) Calculate highest total among these three

q = [90,87,65,67,89]
h = [96,97,95,69,99]
a = [99,98,100,76,49]
mark = [q,h,a]
no = len(mark[0])
high = 0
k = 1
for i in mark:
    total = 0
    for j in i:
        total+=j
    if total>high:
        high = total
        index = k
    k+=1
print(f'substring {index} is high')

Output:
substring 2 is high

PYTHON - APPEND(),INSERT() AND EXTEND()

Keerti Sadana S — Mon, 21 Sep 2026 16:07:21 +0000

Append:
The append() method in Python is used to add a single element to the end of a list.

Example:

l=[]
l.append('abcd')
l.append(1234)
l.append(True)
l.append(5.4)
print(l)

Output:
['abcd', 1234, True, 5.4]

Insert:
-> To insert an item at a specific position in a Python list, use the list.insert(index, element) method.
-> This method modifies the original list in place and does not return a new list.

Example:

l = ['abcd',1234,True, 5.4]

l.insert(1, 'dhanush')
print(l)

l.insert(-2, 'vinoth m')
print(l)

l.insert(-101, 'akilan')
print(l)

Output:
['abcd', 'dhanush', 1234, True, 5.4]
['abcd', 'dhanush', 1234, 'vinoth m', True, 5.4]
['akilan', 'abcd', 'dhanush', 1234, 'vinoth m', True, 5.4]

Nested list:

q = [90,87,65,67,89]
h = [96,97,95,69,99]
a = [99,98,100,76,49]

marks = [q,h,a]
print(marks)

Output:
[[90, 87, 65, 67, 89], [96, 97, 95, 69, 99], [99, 98, 100, 76, 49]]

Extend():
-> The extend() method is used to add all elements from another iterable to the end of a list.
-> It updates the original list by adding each element one by one.

l2 = []
l2.extend('pqrs')
print(l2)

Output:
['p', 'q', 'r', 's']

Append VS Insert VS Extend:

PYTHON - LIST

Keerti Sadana S — Mon, 21 Sep 2026 15:49:28 +0000

-> A list is a built-in data structure used to store an ordered collection of items.
-> They are dynamic, resizable and capable of storing multiple data types.
-> Lists are mutable in Python.
-> This means that once a list is created, we can modify it by adding, removing or changing elements without creating a new list.
-> A list is an index-based data structure.

1) Can we have duplicates objects/elements in a list?
Yes, we can.
Eg: grocery_list = ['soap', 12, 'soap', True, 'rice', 'veggies',4.5]

Sample Program:

name = 'muthu'
name = 'M' + name[1:]
print(name)

Output:
Muthu

Example for Mutablity:

grocery_list = ['soap', 12, True, 'rice', 'veggies',4.5]
grocery_list[0] = 'shampoo'
print(grocery_list)

Output:
['shampoo', 12, True, 'rice', 'veggies', 4.5]

List Properties:
1) A list is a group of individual elements in a single entity
2) In a list, Insertion order is maintained.
3) List is Index / Subscript based.
4) Heterogeneous elements are permitted in a list
5) List Elements are Mutable.

PYTHON - STRING MANIPULATION 2

Keerti Sadana S — Fri, 18 Sep 2026 17:51:19 +0000

Anagram

word1 = input('Enter word: ')
word2 = input('Enter word: ')
if len(word1) != len(word1):
    print('Not Anagram')
else:
    for letter in word1:
        if word1.count(letter) != word2.count(letter):
            print('Not Anagram')
            break
    else:
        print('Anagram')

Output:
Enter word: cat
Enter word: act
Anagram

Rotation:

word = 'abcd' 
for i in range(len(word)):
    rotate = word[1:]+word[0]
    word = rotate
    print(rotate)

Output:
bcda
cdab
dabc
abcd

PYTHON - PASSWORD VALIDATOR AND GENERATOR

Keerti Sadana S — Fri, 18 Sep 2026 17:20:50 +0000

Password Validator:

password = input('Enter Password: ')
if (len(password)<8):
    print('Password should contain at least 8 letters')
elif not any(i.isupper() for i in password):
    print('Password should contain at least 1 uppercase')
elif not any(i.islower() for i in password):
    print('Password should contain at least 1 lowercase')
elif not any(i.isdigit() for i in password):
    print('Password should contain at least 1 digit')
elif not any(not i.isalnum() for i in password):
    print('Password should contain at least 1 special character')
else:
    print('Valid Password')

Output:
Enter Password: Ammu@298
Valid Password

Enter Password: Ammu2345
Password should contain at least 1 special character

Password Generator:

from random import choice
from string import ascii_lowercase,ascii_uppercase,digits
len = int(input('Enter Password Length: '))
letters = ascii_lowercase+ascii_uppercase+digits
password = ''
for i in range(len):
    password += choice(letters)
print(password)

Output:
Enter Password Length: 5
rBMtk

PYTHON - STRING MANIPULATION (COUNT)

Keerti Sadana S — Wed, 16 Sep 2026 18:45:57 +0000

1) Count of Each Letter in a given String

name = 'keertisadana'
lst = list(name)
i = 0
while i < len(lst):
    count = 0
    key = lst[i]
    j = i
    while j < len(lst):
        if key == lst[j] and key != '*':
            count+=1
            lst[j] = '*'
        j+=1
    if key != '*':
        print(key , 'is present', count,' times')
    i+=1

Output:
k is present 1 times
e is present 2 times
r is present 1 times
t is present 1 times
i is present 1 times
s is present 1 times
a is present 3 times
d is present 1 times
n is present 1 times

2) Duplicate letters

name = 'keertisadana'
lst = list(name)
i = 0
while i < len(lst):
    count = 0
    key = lst[i]
    j = i
    while j < len(lst):
        if key == lst[j] and key != '*':
            count+=1
            lst[j] = '*'
        j+=1
    if key != '*' and count > 1:
        print(key , ' is present',count,' times')
    i+=1

Output:
e is present 2 times
a is present 3 times

3) Non-duplicate letters

name = 'keertisadana'
lst = list(name)
i = 0
while i < len(lst):
    count = 0
    key = lst[i]
    j = i
    while j < len(lst):
        if key == lst[j] and key != '*':
            count+=1
            lst[j] = '*'
        j+=1
    if key != '*' and count == 1:
        print(key , ' is present',count,' times')
    i+=1

Output:
k is present 1 times
r is present 1 times
t is present 1 times
i is present 1 times
s is present 1 times
d is present 1 times
n is present 1 times

4) Duplicate letters Count

name = 'keertisadana'
lst = list(name)
i = 0
dup = 0
while i < len(lst):
    count = 0
    key = lst[i]
    j = i
    while j < len(lst):
        if key == lst[j] and key != '*':
            count+=1
            lst[j] = '*'
        j+=1
    if key != '*' and count > 1:
        dup+=1
    i+=1 
print(dup , 'duplicates letters')

Output:
2 duplicates letters

5) Non-duplicate letters Count

name = 'keertisadana'
lst = list(name)
i = 0
n_dup = 0
while i < len(lst):
    count = 0
    key = lst[i]
    j = i
    while j < len(lst):
        if key == lst[j] and key != '*':
            count+=1
            lst[j] = '*'
        j+=1
    if key != '*' and count == 1:
        n_dup+=1
    i+=1 
print(n_dup , 'non-duplicate letters')

Output:
7 non-duplicate letters

6) All letters are unique or not

word = 'keertisadana'
n_dup = 0
dup = 0
lst = list(word)
i = 0
while i < len (lst):
    key = lst[i]
    count = 1
    j = i+1
    while j<len(lst):
        if key == lst[j] and key != '*':
            lst[j] = '*'
            count+=1
        j+=1
    if key != '*' and count > 1:
        n_dup += 1
    i+=1
if len(word) == n_dup:
    print('All letters are unique')
else:
    print('All letters are not unique')

Output:
All letters are not unique

7) Most Frequent letter

word = 'keertisadana'
lst = list(word)
max_count = 0
most_frequent = ' '
i = 0
while i < len (lst):
    key = lst[i]
    count = 1
    j = i+1
    while j<len(lst):
        if key == lst[j] and key != '*':
            lst[j] = '*'
            count+=1
        j+=1
    if key != '*' and count > max_count:
        max_count = count
        most_frequent = key
    i+=1
print(f"The most frequent letter is '{most_frequent}' appearing {max_count} times.")

Output:
The most frequent letter is 'a' appearing 3 times.

8) First Repeated Character

name = 'keertisadana'
lst = list(name)
i = 0
dup = 0
while i < len(lst):
    count = 0
    key = lst[i]
    j = i
    while j < len(lst):
        if key == lst[j] and key != '*':
            count+=1
            lst[j] = '*'
        j+=1
    if key != '*' and count > 1:
        dup+=1
        break
    i+=1
print(f'first repeated character is {key}')

Output:
first repeated character is e

9) First Non-Repeated Character

name = 'keertisadana'
lst = list(name)
i = 0
n_dup = 0
while i < len(lst):
    count = 0
    key = lst[i]
    j = i
    while j < len(lst):
        if key == lst[j] and key != '*':
            count+=1
            #lst[j] = '*'
        j+=1
    if key != '*' and count == 1:
        n_dup+=1
        break
    i+=1
print(f'first non_repeated character is {key}')

Output:
first non_repeated character is k

10) Last Non-Repeated Character

name = 'keertisadana'
lst = list(name)
i = 0
n_dup = ''
last_rep_letter = ' '
while i < len(lst):
    count = 0
    key = lst[i]
    j = i
    while j < len(lst):
        if key == lst[j] and key != '*':
            count+=1
            lst[j] = '*'
        j+=1
    if key != '*' and count == 1:
        n_dup+=key        
    i+=1
print(f'last non_repeated character is {n_dup[-1]}')

Output:
last non_repeated character is n

11) Last Repeated Character

name = 'keertisadana'
lst = list(name)
i = 0
dup = ''
last_rep_letter = ' '
while i < len(lst):
    count = 0
    key = lst[i]
    j = i
    while j < len(lst):
        if key == lst[j] and key != '*':
            count+=1
            lst[j] = '*'
        j+=1
    if key != '*' and count > 1:
        dup+=key        
    i+=1
print(f'last repeated character is {dup[-1]}')

Output:
last repeated character is a

12) Last Repeated Vowel

name = 'keertisadana'
lst = list(name)
i = 0
vowel = ''
last_rep_letter = ' '
while i < len(lst):
    count = 0
    key = lst[i]
    j = i
    while j < len(lst):
        if key == lst[j] and key != '*':
            count+=1
            lst[j] = '*'
        j+=1
    if (key != '*' and key in 'aeiou') and count > 1:
        vowel+=key        
    i+=1
print(f'last repeated vowel is {vowel[-1]}')

Output:
last repeated vowel is a

PYTHON - ALPHABET PATTERNS

Keerti Sadana S — Wed, 09 Sep 2026 20:02:41 +0000

Square:

for row in range(1,8):
    for col in range (1,8):
        if row == 1 or col == 1 or row == 7 or col == 7:
            print('*',end=' ')
        else:
            print(' ',end=' ')
    print()

Output:

* * * * * * * 
*           * 
*           * 
*           * 
*           * 
*           * 
* * * * * * *

Letter A:

for row in range(1,8):
    for col in range (1,8):
        if row == 1 or col == 1 or row == 4  or col == 7 :
            if (row == 1 and (col == 1 or col == 7)) or (row == 7 and (col == 1 or col == 7)) :
                print(' ',end = ' ')
            else:
                print('*',end=' ')
        else:
            print(' ',end=' ')
    print()

Output:

  * * * * *   
*           * 
*           * 
* * * * * * * 
*           * 
*           *

Letter B:

for row in range(1,8):
    for col in range (1,8):
        if row == 1 or col == 1 or row == 4 or row == 7 or col == 7 :
            if (row == 1 and (col == 7)) or (row == 7 and (col == 7)) or (row == 4 and col == 7):
                print(' ',end = ' ')
            else:
                print('*',end=' ')
        else:
            print(' ',end=' ')
    print()

Output:

* * * * * *   
*           * 
*           * 
* * * * * * 
*           * 
*           * 
* * * * * *

Letter C:

for row in range(1,8):
    for col in range (1,8):
        if row == 1 or col == 1 or row == 7 :
            if (row == 1 and (col == 1 or col == 7)) or (row == 7 and (col == 1 or col == 7)) :
                print(' ',end = ' ')
            else:
                print('*',end=' ')
        else:
            print(' ',end=' ')
    print()

Output:

Letter D:

for row in range(1,8):
    for col in range (1,8):
        if row == 1 or col == 1 or row == 7 or col == 7 :
            if not (row==col) :
                print('*',end=' ')
        else:
            print(' ',end=' ')
    print()

Output:

* * * * * * 
*           * 
*           * 
*           * 
*           * 
*           * 
* * * * * *

Letter E:

for row in range(1,8):
    for col in range (1,8):
        if row == 1 or col == 1 or row == 4 or row == 7  :
            if (row == 1 and (col == 7)) or (row == 7 and (col == 7)) or col == 7:
                print(' ',end = ' ')
            else:
                print('*',end=' ')
        else:
            print(' ',end=' ')
    print()

Output:

* * * * * *   
*             
*             
* * * * * *   
*             
*             
* * * * * *

Letter F:

for row in range(1,8):
    for col in range (1,8):
        if row == 1 or col == 1 or row == 4 :
            print('*',end=' ')
        else:
            print(' ',end=' ')
    print()

Output:

* * * * * * * 
*             
*             
* * * * * * * 
*             
*             
*

Letter G:

for row in range(1,8):
    for col in range (1,8):
        if row == 1 or col == 1 or row == 4 or col == 7 or row == 7 :
            if (row == 1 and (col == 1 or col == 7)) or (row == 7 and (col == 1 or col == 7) or (row == 2 or row == 3) and col == 7) or (row == 4 and col == 2) :
                print(' ',end = ' ')
            else:
                print('*',end=' ')
        else:
            print(' ',end=' ')
    print()

Output:

  * * * * *   
*             
*             
*   * * * * * 
*           * 
*           * 
  * * * * *

Letter H:

for row in range(1,8):
    for col in range (1,8):
        if col == 1 or row == 4 or col == 7  :
            if (row == 1 and (col == 1 or col == 7)) or (row == 7 and (col == 1 or col == 7)) :
                print(' ',end = ' ')
            else:
                print('*',end=' ')
        else:
            print(' ',end=' ')
    print()

Output:

*           * 
*           * 
* * * * * * * 
*           * 
*           *

Letter I:

for row in range(1,8):
    for col in range (1,8):
        if row == 1 or col == 4  or row == 7  :
            if (row == 1 and (col == 1 or col == 7)) or (row == 7 and (col == 1 or col == 7)) :
                print(' ',end = ' ')
            else:
                print('*',end=' ')
        else:
            print(' ',end=' ')
    print()

Output:

Letter J:

for row in range(1,8):
    for col in range (1,8):
        if row == 1 or col == 4  or row == 7  :
            if (row == 1 and (col == 1 or col == 7)) or (row == 7 and (col == 1 or col == 7)) or (row == 7 and (col == 4 or col==5 or col == 6)) :
                print(' ',end = ' ')
            else:
                print('*',end=' ')
        else:
            print(' ',end=' ')
    print()

Output:

Letter L:

for row in range(1,8):
    for col in range (1,8):
        if row == 7 or col == 1    :
            if (row == 1 and ( col == 7)) or (row == 7 and ( col == 7))  :
                print(' ',end = ' ')
            else:
                print('*',end=' ')
        else:
            print(' ',end=' ')
    print()

Output:

*             
*             
*             
*             
*             
*             
* * * * * *

Letter M:

for row in range(1,8):
    for col in range(1,8):
        if col == 1 or col == 7 or row == col or row+col==8:
            if (row == 5 and (col == 3 or col == 5)) or (row == 6 and (col == 2 or col == 6)):
                print(" ", end=' ')
            else:
                print('*',end=' ')
        else:
            print(" ", end=' ')
    print()

Output:

*           * 
* *       * * 
*   *   *   * 
*     *     * 
*           * 
*           * 
*           *

Letter N:

for row in range(1,8):
    for col in range(1,8):
        if col == 1 or col == 7 or row == col or row+col==8:
            if (row == 5 and (col == 3 )) or (row == 6 and (col == 2 )) or (row == 3 and col == 5) or (row == 2 and col == 6):
                print(" ", end=' ')
            else:
                print('*',end=' ')
        else:
            print(" ", end=' ')
    print()

Output:

*           * 
* *         * 
*   *       * 
*     *     * 
*       *   * 
*         * * 
*           *

Letter O:

for row in range(1,8):
    for col in range (1,8):
        if row == 1 or col == 1 or row == 7 or col == 7 :
            if (row == 1 and (col == 1 or col == 7)) or (row == 7 and (col == 1 or col == 7)):
                print(' ',end = ' ')
            else:
                print('*',end=' ')
        else:
            print(' ',end=' ')
    print()

Output:

  * * * * *   
*           * 
*           * 
*           * 
*           * 
*           * 
  * * * * *

Letter P:

for row in range(1,8):
    for col in range (1,8):
        if row == 1 or col == 1 or row == 4 or col == 7   :
            if (row == 1 and ( col == 7)) or ((row == 4 or row == 7) and (col == 7)) or ((row == 5 or row == 6) and col == 7)  :
                print(' ',end = ' ')
            else:
                print('*',end=' ')
        else:
            print(' ',end=' ')
    print()

Output:

* * * * * *   
*           * 
*           * 
* * * * * *   
*             
*             
*

Letter R:

for row in range(1,8):
    for col in range (1,8):
        if row == 1 or col == 1 or row == 4 or col == 7 or row == col or row+col==8  :
            if (row == 1 and ( col == 7)) or ((row == 4 ) and (col == 7)) or ((row == 5 or row == 6) and col == 7) or (row == 5 and (col == 3 )) or (row == 6 and (col == 2 )) or (row == 3 and col == 5) or (row == 2 and col == 6) or (row == 2 and col == 2) or ( row == 3 and col == 3):
                print(' ',end = ' ')
            else:
                print('*',end=' ')
        else:
            print(' ',end=' ')
    print()

Output:

* * * * * *   
*           * 
*           * 
* * * * * *   
*       *     
*         *   
*           *

Letter S:

for row in range(1,8):
    for col in range (1,8):
        if row == 1 or col == 1 or row == 4 or col == 7 or row == 7  :
            if (row == 1 and (col == 1 or col == 7)) or ((row == 7 or row == 4) and (col == 1 or col == 7)) or ((row == 2 or row == 3) and col == 7) or ((row == 5 or row == 6 ) and col == 1)  :
                print(' ',end = ' ')
            else:
                print('*',end=' ')
        else:
            print(' ',end=' ')
    print()

Output:

Letter T:

for row in range(1,8):
    for col in range (1,8):
        if row == 1 or col == 4    :
            if (row == 1 and (col == 1 or col == 7)) or (row == 7 and (col == 1 or col == 7))  :
                print(' ',end = ' ')
            else:
                print('*',end=' ')
        else:
            print(' ',end=' ')
    print()

Output:

Letter U:

for row in range(1,8):
    for col in range (1,8):
        if col == 1  or col == 7 or row == 7  :
            if (row == 7 and (col == 1 or col == 7))   :
                print(' ',end = ' ')
            else:
                print('*',end=' ')
        else:
            print(' ',end=' ')
    print()

Output:

*           * 
*           * 
*           * 
*           * 
*           * 
*           * 
  * * * * *

Letter V:

for row in range(1,8):
    for col in range(1,8):
        if   row == col or row+col==8:
            if (row == 5 and (col == 3 or col == 5)) or (row == 6 and (col == 2 or col == 6) or row == 7 ):
                print(" ", end=' ')
            else:
                print('*',end=' ')
        else:
            print(" ", end=' ')
    print()

Output:

*           * 
  *       *   
    *   *     
      *

Letter X:

for row in range(1,8):
    for col in range(1,8):
        if  row == col or row+col==8:  
            print("*", end=' ')
        else:
            print(" ", end=' ')
    print()

Output:

*           * 
  *       *   
    *   *     
      *       
    *   *     
  *       *   
*           *

Letter Y:

for row in range(1,8):
    for col in range(1,8):
        if   col == 4 or row == col or row+col==8:
            if (row == 5 and (col == 3 or col == 5)) or (row == 6 and (col == 2 or col == 6) or row == 7 or (row == 1 and col == 4) or (row == 2 and col == 4) or (row == 3 and col ==4)):
                print(" ", end=' ')
            else:
                print('*',end=' ')
        else:
            print(" ", end=' ')
    print()

Output:

*           * 
  *       *   
    *   *     
      *       
      *       
      *

Letter Z:

for row in range(1,8):
    for col in range(1,8):
        if row == 1 or row == 7  or row+col==8:
            print('*',end=' ')
        else:
            print(" ", end=' ')
    print()

Output:

* * * * * * * 
          *   
        *     
      *       
    *         
  *           
* * * * * * *

** Number 3:**

for row in range(1,8):
    for col in range (1,8):
        if row == 1  or row == 4 or row == 7 or col == 7 :
            if (row == 1 and (col == 7)) or (row == 7 and (col == 7)):
                print(' ',end = ' ')
            else:
                print('*',end=' ')
        else:
            print(' ',end=' ')
    print()

Output:

* * * * * *   
            * 
            * 
* * * * * * * 
            * 
            * 
* * * * * *

Number 6:

for row in range(1,8):
    for col in range (1,8):
        if row == 1 or col == 1 or row == 4 or col == 7 or row == 7 :
            if (row == 1 and (col == 1 or col == 7)) or (row == 7 and (col == 1 or col == 7) or (row == 2 or row == 3) and col == 7) :
                print(' ',end = ' ')
            else:
                print('*',end=' ')
        else:
            print(' ',end=' ')
    print()

Output:

  * * * * *   
*             
*             
* * * * * * * 
*           * 
*           * 
  * * * * *

Number 8:

for row in range(1,8):
    for col in range (1,8):
        if row == 1 or col == 1 or row == 4 or row == 7 or col == 7 :
            print('*',end=' ')
        else:
            print(' ',end=' ')
    print()

Output:

* * * * * * * 
*           * 
*           * 
* * * * * * * 
*           * 
*           * 
* * * * * * *

PYTHON - STRING METHODS EXAMPLES

Keerti Sadana S — Wed, 09 Sep 2026 17:37:33 +0000

Upper():

str1 =  "geeksforgeeks"
print(str1.upper())

Output:
GEEKSFORGEEKS

Lower():

str = "GEEKSFORGEEKS"
print(str.lower())

Output:
geeksforgeeks

Capitalize():

str1 =  "geeks for geeks"
print(str1.capitalize())

Output:
Geeks for geeks

Title():

str1 =  "geeks for geeks"
print(str1.title())

Output:
Geeks For Geeks

Split():

str1 =  "geeks for geeks"
print(str1.split())

Output:
['geeks', 'for', 'geeks']

Join():

lst = ["Geeks", "For", "Geeks"]
print(' '.join(lst))

Output:
Geeks For Geeks

Startswith():

str = "Kite"
print(str.startswith('K'))

Output:
True

Endswith():

str = "Kite"
print(str.endswith('e'))

Output:
True

Casefold():

str = "GEEKSFORGEEKS"
print(str.casefold())

Output:
geeksforgeeks

Swapcase():

str = "Kite"
print(str.swapcase())

Output:
kITE

Strip():

text = "   \n  Hello, Python!   \t "
cleaned = text.strip()
print(f"Original: '{text}'")
print(f"Cleaned:  '{cleaned}'")

Output:
Original: '

Hello, Python! '
Cleaned: 'Hello, Python!'

Lstrip():

text = "   \n\t  Hello World!   "
print(text.lstrip())

Output:
Hello World!

Rstrip():

text = "Hello World \n \t"
print(f"'{text.rstrip()}'")

Output:
'Hello World'

Isspace():

space = '   '
print(space.isspace())

Output:
True

Isalnum():

alnum = 'hi5'
print(alnum.isalnum())

Output:
True

Isnumeric:

num = '½'
print(num.isnumeric())

Output:
True

Isdigit():

num = '49'
print(num.isdigit())

Output:
True

Format():

print('{0}, {1}, {2}'.format('a', 'b', 'c'))
print('{}, {}, {}'.format('a', 'b', 'c'))  
print('{2}, {1}, {0}'.format('a', 'b', 'c'))
print('{2}, {1}, {0}'.format(*'abc'))    
print('{0}{1}{0}'.format('abra', 'cad'))

Output:
a, b, c
a, b, c
c, b, a
c, b, a
abracadabra

PYTHON - STRING METHOD EXPLANATIONS

Keerti Sadana S — Mon, 07 Sep 2026 15:50:11 +0000

About Strings:
-> Strings are sequences of characters written inside quotes.
-> They can include letters, numbers, symbols and spaces.
-> Python does not have a separate character type.
-> Strings are indexed sequences.
-> Positive indices start at 0 from the left; negative indices start at -1 from the right, as represented in the image:

-> Strings are immutable, meaning their values cannot be changed after creation.
-> Any modification to a string creates a new string instead of altering the original one.

What is Immutability?
Existing memory won't be affected. Instead, the change will be updated in new memory.

HashCode:
HashCode is the hexadecimal value of the address.
It is called as hash().

Garbage Collection:
-> An unused object, memory, or function is known as garbage.
-> The process is called garbage collection
-> To use garbage collection functions, import the gc module

Slicing:
-> Slicing is a way to extract a portion of a string by specifying the start and end indices.
Syntax:
str_name[start, stop, step]

Explanation:
-> start - Starting number
-> stop - Ending number + 1
-> step - Increment / Decrement

name = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ'
print(name[0:26])
print()
print(name[0:26:2])
print()
print(name[0:26:3])
print()
print(name[:])
print()
print(name[::2])
print()
print(name[::3])
print()
print(name[5:10])
print()
print(name[:10])
print()
print(name[20:])
print()
print(name[5::2])
print()
print(name[-1::-1])
print()
print(name[::-1])
print()

Output:
ABCDEFGHIJKLMNOPQRSTUVWXYZ

ACEGIKMOQSUWY

ADGJMPSVY

ABCDEFGHIJKLMNOPQRSTUVWXYZ

ACEGIKMOQSUWY

ADGJMPSVY

FGHIJ

ABCDEFGHIJ

UVWXYZ

FHJLNPRTVXZ

ZYXWVUTSRQPONMLKJIHGFEDCBA

String Functions:

-> upper() - makes the full string uppercase
-> lower() - makes the full string lowercase
-> capitalize() - only the first letter becomes uppercase
-> title() - capitalises the first letter of every word.
-> split() - breaks a string into a list of smaller strings based on a separator
-> join() - merges a list or iterable of strings into one single string, using the host string as the connector.
-> startswith() - returns True if the string begins with the specified value;
-> endswith() - returns True if the string ends with the specified value.
-> casefold() - used to convert a string to lowercase. It is similar to the Python lower() string method, but it removes all the case distinctions present in a string.
-> swapcase() - swaps uppercase letters to lowercase, and lowercase letters to uppercase.
-> strip() - removes all leading and trailing whitespace
-> lstrip() - removes whitespace (or specific characters) only from the left (start) of the string.
-> rstrip() - removes whitespace (or specific characters) only from the right (end) of the string.
-> isspace() - returns True if all characters in the string are whitespace.
-> isalnum() - returns True if all characters in the string are alphanumeric (letters or numbers).
-> isdigit() - Returns True if all characters are basic digits (0-9) and certain Unicode subscripts/superscripts.
-> isnumeric() - Returns True if all characters are numeric, which includes digits, fractions, Roman numerals, and foreign currency numerals.
-> format() - used to inject dynamic values into template strings.
Refer to the examples for the above methods:
https://dev.to/keerti_sadanas_d3bbb8924/python-string-methods-examples-4im