| 1. Import NumPy | Easy |
| 2. NumPy Version | Easy |
| 3. Null Vector of Size 10 | Easy |
| 4. Memory Size of an Array | Easy |
| 5. Documentation of np.add | Easy |
| 6. Null Vector, Fifth Value 1 | Easy |
| 7. Range Vector 10–49 | Easy |
| 8. Reverse a Vector | Easy |
| 9. 3×3 Matrix 0–8 | Easy |
| 10. Indices of Non-Zero Elements | Easy |
| 11. Identity Matrix | Easy |
| 12. 3×3×3 Random Array | Easy |
| 13. Min and Max | Easy |
| 14. Mean Value | Easy |
| 15. 1 on Border, 0 Inside | Easy |
| 16. Add a Zero Border | Easy |
| 17. NaN Expression Results | Easy |
| 18. Values Below the Diagonal | Easy |
| 19. Checkerboard Pattern | Easy |
| 20. Unravel 100th Index | Easy |
| 21. Checkerboard with tile() | Easy |
| 22. Normalize a Matrix | Easy |
| 23. RGBA dtype Size | Easy |
| 24. Matrix Product | Easy |
| 25. Negate Elements 3–8 | Easy |
| 26. Builtin sum vs np.sum | Easy |
| 27. Which Expressions Are Legal? | Easy |
| 28. Results of Edge Expressions | Easy |
| 29. Round Away From Zero | Easy |
| 30. Common Values | Easy |
| 31. Ignore NumPy Warnings | Easy |
| 32. sqrt(-1) vs emath.sqrt(-1) | Easy |
| 33. Yesterday and Tomorrow | Easy |
| 34. Dates in July 2016 | Medium |
| 35. Compute ((A+B)*(-A/2)) | Medium |
| 36. Integer Part | Medium |
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| 37. Rows Ranging 0–4 | Medium |
| 38. Build Array from Generator | Easy |
| 39. Vector 0–1 Both Excluded | Medium |
| 40. Sort a Vector | Medium |
| 41. Sum with add.reduce | Medium |
| 42. Are Two Arrays Equal? | Medium |
| 43. Make an Array Read-Only | Medium |
| 44. Cartesian to Polar | Medium |
| 45. Replace Max with 0 | Medium |
| 46. Coordinate Grid | Medium |
| 47. Cauchy Matrix Determinant | Medium |
| 48. Min/Max of int8 | Medium |
| 49. Full Array as String | Medium |
| 50. Closest Value to a Scalar | Medium |
| 51. Position + Color Struct | Medium |
| 52. Point-by-Point Distances | Medium |
| 53. Float32 to Int32 In Place | Medium |
| 54. Parse a Messy CSV | Medium |
| 55. Enumerate a 2D Array | Medium |
| 56. 2D Gaussian Array | Medium |
| 57. Place p Elements Randomly | Medium |
| 58. Subtract Row Means | Medium |
| 59. Sort by nth Column | Medium |
| 60. Has Null Columns? | Medium |
| 61. Nearest Value | Medium |
| 62. Sum via Iterator | Medium |
| 63. Array with a Name | Medium |
| 64. Add 1 at Indexed Positions | Hard |
| 65. Accumulate by Index List | Hard |
| 66. Count Unique Colors | Medium |
| 67. Sum Over Last Two Axes | Hard |
| 68. Means of Subsets | Hard |
| 69. Diagonal of a Dot Product | Hard |
| 70. Interleave 3 Zeros | Hard |
| 71. Multiply (5,5,3) by (5,5) | Hard |
| 72. Swap Two Rows | Hard |
| 73. Unique Triangle Segments | Hard |
| 74. Invert a bincount | Hard |
| 75. Sliding Window Average | Hard |
| 76. Rolling Windows (shift by 1) | Hard |
| 77. Negate Float Array In Place | Hard |
| 78. Distance Point to Lines | Hard |
| 79. Distance Points to Lines | Hard |
| 80. Centered Subpart with Fill | Hard |
| 81. Generate Shifted Rows | Hard |
| 82. Matrix Rank | Hard |
| 83. Most Frequent Value | Medium |
| 84. All Contiguous 3×3 Blocks | Hard |
| 85. Make a Matrix Symmetric | Hard |
| 86. Sum of p Matrix Products | Hard |
| 87. Block-Sum (4×4 blocks) | Hard |
| 88. Game of Life Step | Hard |
| 89. n Largest Values | Hard |
| 90. Cartesian Product | Hard |
| 91. Record Array from Array | Hard |
| 92. Cube Each Element | Hard |
| 93. Rows Containing Each Row of B | Hard |
| 94. Rows with Unequal Values | Hard |
| 95. Ints to Binary Matrix | Hard |
| 96. Extract Unique Rows | Hard |
| 97. Outer Product with einsum | Hard |
| 98. Equidistant Path Sampling | Hard |
| 99. Multinomial Rows | Hard |
| 100. Bootstrap Confidence Interval | Hard |
| 101. Full Array Like a Prototype | Easy |
| 102. Reproducible Random Integers (Generator API) | Easy |
| 103. Binomial Draws (Generator API) | Medium |
| 104. Save and Load a .npy Array | Easy |
| 105. Save Multiple Named Arrays with savez | Medium |
| 106. Selective CSV Import | Medium |
| 107. Impute Missing Values with the Column Mean | Medium |
| 108. Delete Rows and Columns | Easy |
| 109. Sort Rows by a Given Column | Easy |
| 110. Locate Elements Matching a Condition | Easy |
| 111. Stack Two Vectors as Rows | Easy |
| 112. Concatenate Two Vectors End-to-End | Easy |
| 113. Stack Two Matrices Along a New Axis | Medium |
| 114. Count Occurrences of Each Unique Value | Easy |
| 115. Index of First Occurrence of Each Unique Value | Easy |
| 116. Weighted Average | Easy |
| 117. Correlation Matrix Between Rows | Medium |
| 118. Histogram Bin Counts | Easy |
| 119. Peak-to-Peak Range per Row | Easy |
| 120. Strip Prefixes and Map Categories to Codes | Medium |
| 121. Row-wise Stable Softmax | Easy |
| 122. One-Hot Encode an Index Array | Easy |
| 123. Dense Layer Forward with Leaky ReLU | Easy |
| 124. Padding Mask from Sequence Lengths | Easy |
| 125. Layer Normalization Forward | Easy |
| 126. Top-k Accuracy | Easy |
| 127. Cross-Entropy Loss Straight from Logits | Medium |
| 128. Batch Norm Forward with Running Stats | Medium |
| 129. One Lloyd Step of k-Means | Medium |
| 130. kNN Predict with a Deterministic Tie-Break | Medium |
| 131. Confusion Matrix and Macro F1 | Medium |
| 132. Pairwise IoU Matrix Between Box Sets | Medium |
| 133. Logistic Loss and Gradient, Vectorized | Medium |
| 134. Ridge Regression in Closed Form | Medium |
| 135. Max-Pool Forward with Stride | Medium |
| 136. Gradient of Softmax Cross-Entropy | Hard |
| 137. Backprop Gradients for a Two-Layer MLP | Hard |
| 138. Scaled Dot-Product Attention, Causal | Hard |
| 139. Greedy Non-Maximum Suppression | Hard |
| 140. ROC AUC by Rank Statistic, with Ties | Hard |
| 141. Coalesce Two Rating Columns | Easy |
| 142. Drop Rows Containing Any Missing Value | Easy |
| 143. Winsorize at Given Percentiles | Easy |
| 144. Month-over-Month Growth Rate | Easy |
| 145. Average Order Value per Customer | Medium |
| 146. Percentile Rank Each Value | Medium |
| 147. Number the Rows Within Each Group | Medium |
| 148. Forward-Fill Missing Values | Medium |
| 149. Convert Amounts via a Rate Lookup | Medium |
| 150. Standardize Each Column Safely | Medium |
| 151. Top-N Rows per Category | Hard |
| 152. Longest Streak of Consecutive Active Days | Hard |
| 153. Classify Each Indexing Form as View or Copy | Medium |
| 154. Find the Unit-Stride Axis | Medium |
| 155. Resolve a Broadcast Shape by Hand | Medium |
| 156. Which Reductions Silently Change dtype | Medium |
| 157. may_share_memory vs shares_memory | Medium |
| 158. Predict Result dtypes Under NEP 50 | Hard |
| 159. In-Place vs Out-of-Place Mixed dtypes | Hard |
| 160. Build a Broadcast View With a Zero Stride | Hard |
| 161. The reduceat Non-Monotonic Trap | Hard |
| 162. Log Returns from a Price Series | Easy |
| 163. Interpolate a Curve with Flat Extrapolation | Easy |
| 164. Maximum Drawdown with Peak and Trough | Medium |
| 165. Rolling Z-Score Over a Trailing Window | Medium |
| 166. RiskMetrics EWMA Volatility | Medium |
| 167. OLS Beta and R-Squared via Least Squares | Medium |
| 168. Global Minimum-Variance Portfolio Weights | Medium |
| 169. Attach the Prevailing Quote to Each Trade | Hard |
| 170. Monte Carlo Call with Antithetic Variates | Hard |