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102 problems across Python basics, Pandas, NumPy, and algorithm classics. Runs locally via WebAssembly — no install, no login, no per-run cost. Sign in to track which you've solved.

68
Easy
32
Medium
2
Hard

Difficulty

Topic

Showing 102 of 102 problems

Problem	Topic	Difficulty	Action
01. Hello, Python Python BasicsEasy	Python Basics	Easy	Solve →
02. Variables and types Python BasicsEasy	Python Basics	Easy	Solve →
03. Arithmetic operators Python BasicsEasy	Python Basics	Easy	Solve →
04. f-strings Python BasicsEasy	Python Basics	Easy	Solve →
05. Cast a string to int Python BasicsEasy	Python Basics	Easy	Solve →
06. Boolean operators Python BasicsEasy	Python Basics	Easy	Solve →
07. Comparison chain Python BasicsEasy	Python Basics	Easy	Solve →
08. Swap two variables Python BasicsEasy	Python Basics	Easy	Solve →
09. Format rupees Python BasicsEasy	Python Basics	Easy	Solve →
10. Min and max of three numbers Python BasicsEasy	Python Basics	Easy	Solve →
11. Absolute value Python BasicsEasy	Python Basics	Easy	Solve →
12. Rounding decimals Python BasicsEasy	Python Basics	Easy	Solve →
13. Multiple assignment Python BasicsEasy	Python Basics	Easy	Solve →
14. String repetition Python BasicsEasy	Python Basics	Easy	Solve →
15. Celsius to Fahrenheit Python BasicsEasy	Python Basics	Easy	Solve →
16. If/elif/else — grade letter Control FlowEasy	Control Flow	Easy	Solve →
17. For loop over range Control FlowEasy	Control Flow	Easy	Solve →
18. Lists, loops, conditionals Control FlowEasy	Control Flow	Easy	Solve →
19. While loop countdown Control FlowEasy	Control Flow	Easy	Solve →
20. FizzBuzz (1 to 15) Control FlowEasy	Control Flow	Easy	Solve →
21. Sum of 1 to N Control FlowEasy	Control Flow	Easy	Solve →
22. Multiplication table 5x5 Control FlowEasy	Control Flow	Easy	Solve →
23. break and continue Control FlowEasy	Control Flow	Easy	Solve →
24. Is leap year? Control FlowEasy	Control Flow	Easy	Solve →
25. enumerate() Control FlowEasy	Control Flow	Easy	Solve →
26. zip() two lists Control FlowEasy	Control Flow	Easy	Solve →
27. Reverse range Control FlowEasy	Control Flow	Easy	Solve →
28. Functions — average FunctionsEasy	Functions	Easy	Solve →
29. Default arguments FunctionsEasy	Functions	Easy	Solve →
30. *args — variable arguments FunctionsMedium	Functions	Medium	Solve →
31. **kwargs — keyword arguments FunctionsMedium	Functions	Medium	Solve →
32. Lambda — sort by length FunctionsMedium	Functions	Medium	Solve →
33. Recursive factorial FunctionsMedium	Functions	Medium	Solve →
34. map() — apply a function FunctionsMedium	Functions	Medium	Solve →
35. filter() — keep positives FunctionsEasy	Functions	Easy	Solve →
36. Closure — make a counter FunctionsMedium	Functions	Medium	Solve →
37. Docstrings FunctionsEasy	Functions	Easy	Solve →
38. String length StringsEasy	Strings	Easy	Solve →
39. Upper and lower case StringsEasy	Strings	Easy	Solve →
40. Reverse a string StringsEasy	Strings	Easy	Solve →
41. Count vowels StringsEasy	Strings	Easy	Solve →
42. Palindrome check StringsEasy	Strings	Easy	Solve →
43. Split a sentence into words StringsEasy	Strings	Easy	Solve →
44. Join words StringsEasy	Strings	Easy	Solve →
45. Replace substring StringsEasy	Strings	Easy	Solve →
46. Strip whitespace StringsEasy	Strings	Easy	Solve →
47. startswith / endswith StringsEasy	Strings	Easy	Solve →
48. Count occurrences StringsEasy	Strings	Easy	Solve →
49. Title-case a sentence StringsEasy	Strings	Easy	Solve →
50. Append + insert ListsEasy	Lists	Easy	Solve →
51. List slicing ListsEasy	Lists	Easy	Solve →
52. List comprehension — squares ListsEasy	Lists	Easy	Solve →
53. List comprehension — filter evens ListsEasy	Lists	Easy	Solve →
54. Sort a list ListsEasy	Lists	Easy	Solve →
55. Remove duplicates (preserve order) ListsMedium	Lists	Medium	Solve →
56. Flatten a nested list ListsMedium	Lists	Medium	Solve →
57. Sum and max of a list ListsEasy	Lists	Easy	Solve →
58. Count occurrences ListsEasy	Lists	Easy	Solve →
59. Second-largest element ListsMedium	Lists	Medium	Solve →
60. Dict basics DictsEasy	Dicts	Easy	Solve →
61. Update a dict DictsEasy	Dicts	Easy	Solve →
62. Iterate keys and values DictsEasy	Dicts	Easy	Solve →
63. dict.get with default DictsEasy	Dicts	Easy	Solve →
64. Count word frequencies DictsMedium	Dicts	Medium	Solve →
65. Dict comprehension DictsMedium	Dicts	Medium	Solve →
66. Sort dict by value DictsMedium	Dicts	Medium	Solve →
67. Nested dict access DictsMedium	Dicts	Medium	Solve →
68. Set basics SetsEasy	Sets	Easy	Solve →
69. Set union SetsEasy	Sets	Easy	Solve →
70. Set intersection SetsEasy	Sets	Easy	Solve →
71. Set difference SetsEasy	Sets	Easy	Solve →
72. Set membership check SetsEasy	Sets	Easy	Solve →
73. Tuple unpacking TuplesEasy	Tuples	Easy	Solve →
74. Tuples are immutable TuplesEasy	Tuples	Easy	Solve →
75. Return multiple values TuplesEasy	Tuples	Easy	Solve →
76. Define a class OOPEasy	OOP	Easy	Solve →
77. Instance method OOPEasy	OOP	Easy	Solve →
78. Inheritance OOPMedium	OOP	Medium	Solve →
79. super() — call parent init OOPMedium	OOP	Medium	Solve →
80. __repr__ method OOPMedium	OOP	Medium	Solve →
81. __eq__ — equality OOPMedium	OOP	Medium	Solve →
82. @classmethod OOPMedium	OOP	Medium	Solve →
83. @property OOPMedium	OOP	Medium	Solve →
84. @staticmethod OOPMedium	OOP	Medium	Solve →
85. Name mangling — _private OOPMedium	OOP	Medium	Solve →
86. Fibonacci sequence AlgorithmsEasy	Algorithms	Easy	Solve →
87. Is prime? AlgorithmsEasy	Algorithms	Easy	Solve →
88. Binary search AlgorithmsMedium	Algorithms	Medium	Solve →
89. Two-sum (find pair summing to target) Data StructuresMedium	Data Structures	Medium	Solve →
90. Reverse a list in place AlgorithmsEasy	Algorithms	Easy	Solve →
91. Longest substring without repeating characters AlgorithmsHard	Algorithms	Hard	Solve →
92. GCD (Euclid) AlgorithmsMedium	Algorithms	Medium	Solve →
93. Are two strings anagrams? AlgorithmsMedium	Algorithms	Medium	Solve →
94. Stack with list Data StructuresEasy	Data Structures	Easy	Solve →
95. Queue with deque Data StructuresMedium	Data Structures	Medium	Solve →
96. collections.Counter — top words Data StructuresMedium	Data Structures	Medium	Solve →
97. NumPy — arrays + vectorisation NumPyMedium	NumPy	Medium	Solve →
98. NumPy — mean / std / sum NumPyMedium	NumPy	Medium	Solve →
99. NumPy — reshape NumPyMedium	NumPy	Medium	Solve →
100. Pandas — load a CSV PandasMedium	Pandas	Medium	Solve →
101. Pandas — group + aggregate PandasMedium	Pandas	Medium	Solve →
102. D2C analysis capstone Data AnalysisHard	Data Analysis	Hard	Solve →

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