Python Basic interview Question And Answer

# Python String & Number Programs – Interview Preparation Guide html

Python Interview Programs

1. Check String is Palindrome or Not

Solution 1: Reverse the String & Compare

x = "dalad"

y = x[::-1]

if x == y:
    print("String is palindrome")
else:
    print("Not palindrome")

Output: String is palindrome

Solution 2: Compare Characters from Both Ends

x = "dalad"

is_palindrome = True

for i in range(len(x) // 2):
    if x[i] != x[len(x) - 1 - i]:
        is_palindrome = False
        break

print("Given String is Palindrome:", is_palindrome)

2. Change Character Case in a String

x = "ChAnDaNsInGh"
y = ""

for char in x:
    if char.isupper():
        y += char.lower()
    elif char.islower():
        y += char.upper()

print(y)

Output: cHaNdAnSiNgH

3. Sort a String

Without Using Built-in Method

x = "chandansingh"

char_list = list(x)

for i in range(len(char_list)):
    for j in range(len(char_list)):
        if char_list[i] > char_list[j]:
            char_list[i], char_list[j] = char_list[j], char_list[i]

result = "".join(char_list)

print(result)

Using sorted()

x = "chandansingh"

result = "".join(sorted(x))

print(result)

4. Check Whether Two Strings Have Same Characters

x = "chandansingh"
y = "singhchandan"

result = sorted(x) == sorted(y)

print("Are both strings same:", result)

5. Find the Greatest Number from a List

x = [1, 4, 10, 6, 8, 9, 5]

greatest = x[0]

for num in x:
    if num > greatest:
        greatest = num

print(greatest)

Output: 10

6. Reverse a String

x = "way2testing"
y = ""

for char in x:
    y = char + y

print(y)

Output: gnitset2yaw

7. Reverse a Sentence

x = "i love reading from way2testing"

words = x.split()

result = []

for i in range(len(words)-1, -1, -1):
    result.append(words[i])

print(" ".join(result))

8. Find the Largest Word in a Sentence

x = "I live in India and i like python"

words = x.split()

largest = words[0]

for word in words:
    if len(word) > len(largest):
        largest = word

print(largest)
print(len(largest))

9. Reverse the Sentence and Reverse Each Word

x = "i love reading from way2testing"

words = x.split()

result = []

for i in range(len(words)-1, -1, -1):
    result.append(words[i][::-1])

print(" ".join(result))

Output: gnitset2yaw morf gnidaer evol i

10. Remove Duplicate Characters from String

x = "way2testing"

result = set(x)

print("".join(result))

11. Remove Duplicates and Maintain Sequence

x = "way2testing"

seen = set()

result = []

for char in x:
    if char not in seen:
        seen.add(char)
        result.append(char)

print("".join(result))

Output: way2tesing

12. Find Character Count in a String

x = "way2testing"

count_dict = {}

for char in x:
    if char in count_dict:
        count_dict[char] += 1
    else:
        count_dict[char] = 1

print(count_dict)

13. Find Characters Whose Occurrence is More Than 1

from collections import Counter

x = "way2testing"

counts = Counter(x)

duplicates = {}

for char, count in counts.items():
    if count > 1:
        duplicates[char] = count

print(duplicates)

14. Reverse a Number

x = 123456

output = 0

while x > 0:
    remainder = x % 10
    output = (output * 10) + remainder
    x = x // 10

print(output)

Output: 654321