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What will I learn?


This puzzle makes you efficiently backtrack through a decision tree, and learn to prune this tree based on a heuristic.

Storing your problem to an efficient data structure will help you optimize your solution


Focus on a Puzzle: There Is No Spoon 2 by CyberLemonade


You need to solve a game of Hashiwokakero, building bridges between cells of a grid, forming a graph. In order to solve this problem, you will need an efficient way to store possible solutions for each step, and backtrack through this possibilities in order to find the optimal one.

Solve it

A higher resolution is required to access the IDE


Zion is being attacked from everywhere. The last free humans count on you to enhance the triggering mechanism of the APUs (Armored Personal Unit) in order to give humanity a decisive tactical advantage. Second phase: improve the power supply circuit of the APU without making any short circuit or overheating the system.


This puzzle is part of a series of two exercises proposed during the “There is no Spoon” contest. Before you solve it, try out the first level, « There Is No Spoon - Episode 1 ».

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