Samsung R&d

# Samsung R&D Research Intern – IIT Patna (On-Campus) Technical round. Three DSA questions plus one ML question. Other candidates in the same drive got the same set. ## Round 1 – Technical Introduce yourself. **Decode String.** A string is encoded as `k[encoded_string]`, which means the part inside the brackets repeats exactly k times. Encodings can be nested. Return the decoded string. Example: `3[a2[c]]` → `accaccacc`. The usual approach is a stack holding (repeat count, string built so far). **Longest Consecutive Sequence.** Given an unsorted integer array, return the length of the longest run of consecutive integers in O(n). Example: `[100, 4, 200, 1, 3, 2]` → 4. The usual approach is to put everything in a hash set and only start counting from numbers whose `x - 1` isn't in the set. **Lab placement on a grid.** Cities sit on a grid, and you need to place a lab as far as possible from the nearest city. Given an n×n grid of 1s (cities) and 0s (empty cells), find the empty cell whose Manhattan distance to the nearest 1 is as large as possible and return that distance (-1 if there are no 1s or no 0s). Run a multi-source BFS from every city at once. How do you fix overfitting in a model?