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Frogger's shortest trip

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Frogger's shortest trip is a hard quant coding problem on language knowledge in Cpp / Python.

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Shortest-path problem with custom movement costs

This is a hard coding problem that combines graph construction with shortest-path search. It asks you to model a frog's movement across stones as a weighted graph, where each stone is a node and the cost of each edge depends on the type of jump available.

The core challenge is understanding the two jump mechanics: a cheap fixed-cost "short hop" to a designated nearest neighbor, and a distance-based "long jump" to any stone. You must precompute the nearest neighbor for each stone according to a specific tiebreaking rule, then use Dijkstra's algorithm (or dynamic programming) to find the minimum cost for each query trip. The problem rewards careful implementation in C++ or Python, correct handling of edge cases (boundary stones, tie-breaking), and efficient shortest-path logic.

  • Graph representation and edge weight assignment
  • Precomputation of neighbor relationships
  • Single-source shortest-path queries (Dijkstra)
  • Managing multiple independent trip queries efficiently