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Tower of Hanoi with Rings
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Tower of Hanoi with Rings

EasyPython

Problem

Yochana’s workflow engine needs to generate a valid transfer plan for a stack of five rings. Solve the Tower of Hanoi problem by moving the entire stack from a source peg to a target peg while preserving the ordering rules.

Implement hanoi_moves(n, source, auxiliary, target) and return the minimum sequence of moves.

Formal Specification

  • Input: An integer n, plus three distinct peg names represented as strings: source, auxiliary, and target.
  • Output: A list of strings. Each string must use the format "A -> C", meaning the top ring moves from peg A to peg C.
  • A move may transfer only one ring.
  • A larger ring may never be placed on a smaller ring.
  • The returned sequence must move all n rings from source to target.
  • The sequence must contain the minimum possible number of moves.

Constraints

  • 0 <= n <= 5
  • Peg names are distinct, non-empty strings
  • The output contains exactly 2^n - 1 moves
  • Only one ring is moved per step
  • A larger ring cannot be placed on a smaller ring

Function Signature

def hanoi_moves(n, source, auxiliary, target):
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