Implement it on LeetCode. Space optimization: since each cell only depends on the cell above and to the left, you can use a single row. Update left-to-right, adding the previous row's value (stored in the same position before update). Follow-up: Unique Paths II adds obstacles. Set dp to for obstacle cells.
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$ curl repovive.com/roadmaps/maang-interview-prep/dynamic-programming/unique-paths-implementation
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